Now keeping track of useful relays in ARFlightController, and using that list instead of FlightGlobals in AntennaRelay and ARMapRenderer.
Now keeping track of useful relays in ARFlightController, and using that list instead of FlightGlobals in AntennaRelay and ARMapRenderer.

--- a/ARConfiguration.cs
+++ b/ARConfiguration.cs
@@ -16,6 +16,18 @@
 	[KSPAddon(KSPAddon.Startup.SpaceCentre, false)]
 	public class ARConfiguration : MonoBehaviour
 	{
+		private const string WINDOW_POS_KEY = "configWindowPos";
+		private const string REQUIRE_LOS_KEY = "requireLineOfSight";
+		private const string GRACE_RATIO_KEY = "graceRatio";
+		private const string REQUIRE_PROBE_CONNECTION_KEY = "requireConnectionForControl";
+		private const string FIXED_POWER_KEY = "fixedPowerCost";
+		private const string PRETTY_LINES_KEY = "drawPrettyLines";
+		private const string UPDATE_DELAY_KEY = "updateDelay";
+		private const string USE_ADDITIVE_KEY = "useAdditiveRanges";
+
+		private const string TRACKING_STATION_RANGES_KEY = "TRACKING_STATION_RANGES";
+		private const string RANGE_KEY = "range";
+
 		/// <summary>
 		/// Indicates whether connections require line of sight.
 		/// </summary>
@@ -59,7 +71,45 @@
 		public static bool PrettyLines
 		{
 			get;
-			private set;
+			set;
+		}
+
+		/// <summary>
+		/// Gets the update delay.
+		/// </summary>
+		public static long UpdateDelay
+		{
+			get;
+			private set;
+		}
+
+		/// <summary>
+		/// Gets a value indicating whether AntennaRange will use additive ranges.
+		/// </summary>
+		public static bool UseAdditiveRanges
+		{
+			get;
+			private set;
+		}
+
+		/// <summary>
+		/// Gets Kerbin's relay range based on the current tracking station level.
+		/// </summary>
+		public static double KerbinRelayRange
+		{
+			get;
+			private set;
+		}
+
+		/// <summary>
+		/// Gets Kerbin's nominal relay range based on the current tracking station level.
+		/// </summary>
+		public static double KerbinNominalRange
+		{
+			get
+			{
+				return KerbinRelayRange / 2.8284271247461901d;
+			}
 		}
 
 #pragma warning disable 1591
@@ -67,10 +117,17 @@
 		private bool showConfigWindow;
 		private Rect configWindowPos;
 
+		private string updateDelayStr;
+		private long updateDelay;
+
 		private IButton toolbarButton;
 		private ApplicationLauncherButton appLauncherButton;
 
+		private double[] trackingStationRanges;
+
 		private System.Version runningVersion;
+
+		private bool runOnce;
 
 		private KSP.IO.PluginConfiguration _config;
 		private KSP.IO.PluginConfiguration config
@@ -96,25 +153,79 @@
 			this.configWindowPos = new Rect(Screen.width / 4, Screen.height / 2, 180, 15);
 
 
-			this.configWindowPos = this.LoadConfigValue("configWindowPos", this.configWindowPos);
-
-			ARConfiguration.RequireLineOfSight = this.LoadConfigValue("requireLineOfSight", false);
-
-			ARConfiguration.RadiusRatio = (1 - this.LoadConfigValue("graceRatio", .05d));
+			this.configWindowPos = this.LoadConfigValue(WINDOW_POS_KEY, this.configWindowPos);
+
+			ARConfiguration.RequireLineOfSight = this.LoadConfigValue(REQUIRE_LOS_KEY, false);
+
+			ARConfiguration.RadiusRatio = (1 - this.LoadConfigValue(GRACE_RATIO_KEY, .05d));
 			ARConfiguration.RadiusRatio *= ARConfiguration.RadiusRatio;
 
 			ARConfiguration.RequireConnectionForControl =
-				this.LoadConfigValue("requireConnectionForControl", false);
-
-			ARConfiguration.FixedPowerCost = this.LoadConfigValue("fixedPowerCost", false);
-
-			ARConfiguration.PrettyLines = this.LoadConfigValue("drawPrettyLines", true);
+				this.LoadConfigValue(REQUIRE_PROBE_CONNECTION_KEY, false);
+
+			ARConfiguration.FixedPowerCost = this.LoadConfigValue(FIXED_POWER_KEY, false);
+
+			ARConfiguration.PrettyLines = this.LoadConfigValue(PRETTY_LINES_KEY, true);
+
+			ARConfiguration.UpdateDelay = this.LoadConfigValue(UPDATE_DELAY_KEY, 16L);
+
+			ARConfiguration.UseAdditiveRanges = this.LoadConfigValue(USE_ADDITIVE_KEY, true);
+
+			this.updateDelayStr = ARConfiguration.UpdateDelay.ToString();
 
 			GameEvents.onGameSceneLoadRequested.Add(this.onSceneChangeRequested);
+			GameEvents.OnKSCFacilityUpgraded.Add(this.onFacilityUpgraded);
 
 			Debug.Log(string.Format("{0} v{1} - ARConfiguration loaded!", this.GetType().Name, this.runningVersion));
 
+			ConfigNode[] tsRangeNodes = GameDatabase.Instance.GetConfigNodes(TRACKING_STATION_RANGES_KEY);
+
+			if (tsRangeNodes.Length > 0)
+			{
+				string[] rangeValues = tsRangeNodes[0].GetValues(RANGE_KEY);
+
+				this.trackingStationRanges = new double[rangeValues.Length];
+
+				for (int idx = 0; idx < rangeValues.Length; idx++)
+				{
+					if (!double.TryParse(rangeValues[idx], out this.trackingStationRanges[idx]))
+					{
+						this.LogError("Could not parse value '{0}' to double; Tracking Station ranges may not work!");
+						this.trackingStationRanges[idx] = 0d;
+					}
+				}
+
+				this.Log("Loaded Tracking Station ranges from config: [{0}]", this.trackingStationRanges.SPrint());
+			}
+			else
+			{
+				this.trackingStationRanges = new double[]
+				{
+					51696576d,
+					37152180000d,
+					224770770000d
+				};
+
+				this.LogWarning("Failed to load Tracking Station ranges from config, using hard-coded values: [{0}]",
+					this.trackingStationRanges.SPrint());
+			}
+
+			this.runOnce = true;
+
 			Tools.PostDebugMessage(this, "Awake.");
+		}
+
+		public void Update()
+		{
+			if (
+				this.runOnce &&
+				(ScenarioUpgradeableFacilities.Instance != null || HighLogic.CurrentGame.Mode != Game.Modes.CAREER)
+			)
+			{
+				this.runOnce = false;
+
+				this.SetKerbinRelayRange();
+			}
 		}
 
 		public void OnGUI()
@@ -167,7 +278,7 @@
 				if (configPos != this.configWindowPos)
 				{
 					this.configWindowPos = configPos;
-					this.SaveConfigValue("configWindowPos", this.configWindowPos);
+					this.SaveConfigValue(WINDOW_POS_KEY, this.configWindowPos);
 				}
 			}
 		}
@@ -182,7 +293,7 @@
 			if (requireLineOfSight != ARConfiguration.RequireLineOfSight)
 			{
 				ARConfiguration.RequireLineOfSight = requireLineOfSight;
-				this.SaveConfigValue("requireLineOfSight", requireLineOfSight);
+				this.SaveConfigValue(REQUIRE_LOS_KEY, requireLineOfSight);
 			}
 
 			GUILayout.EndHorizontal();
@@ -197,7 +308,7 @@
 			if (requireConnectionForControl != ARConfiguration.RequireConnectionForControl)
 			{
 				ARConfiguration.RequireConnectionForControl = requireConnectionForControl;
-				this.SaveConfigValue("requireConnectionForControl", requireConnectionForControl);
+				this.SaveConfigValue(REQUIRE_PROBE_CONNECTION_KEY, requireConnectionForControl);
 			}
 
 			GUILayout.EndHorizontal();
@@ -208,7 +319,18 @@
 			if (fixedPowerCost != ARConfiguration.FixedPowerCost)
 			{
 				ARConfiguration.FixedPowerCost = fixedPowerCost;
-				this.SaveConfigValue("fixedPowerCost", fixedPowerCost);
+				this.SaveConfigValue(FIXED_POWER_KEY, fixedPowerCost);
+			}
+
+			GUILayout.EndHorizontal();
+
+			GUILayout.BeginHorizontal();
+
+			bool useAdditive = GUITools.Toggle(ARConfiguration.UseAdditiveRanges, "Use Additive Ranges");
+			if (useAdditive != ARConfiguration.UseAdditiveRanges)
+			{
+				ARConfiguration.UseAdditiveRanges = useAdditive;
+				this.SaveConfigValue(USE_ADDITIVE_KEY, useAdditive);
 			}
 
 			GUILayout.EndHorizontal();
@@ -219,10 +341,26 @@
 			if (prettyLines != ARConfiguration.PrettyLines)
 			{
 				ARConfiguration.PrettyLines = prettyLines;
-				this.SaveConfigValue("drawPrettyLines", prettyLines);
-			}
-
-			GUILayout.EndHorizontal();
+				this.SaveConfigValue(PRETTY_LINES_KEY, prettyLines);
+			}
+
+			GUILayout.EndHorizontal();
+
+			GUILayout.BeginHorizontal();
+
+			GUILayout.Label("Update Delay", GUILayout.ExpandWidth(false));
+
+			this.updateDelayStr = GUILayout.TextField(this.updateDelayStr, 4, GUILayout.Width(40f));
+
+			GUILayout.Label("ms", GUILayout.ExpandWidth(false));
+
+			GUILayout.EndHorizontal();
+
+			if (this.updateDelayStr.Length > 1 && long.TryParse(this.updateDelayStr, out this.updateDelay))
+			{
+				ARConfiguration.UpdateDelay = Math.Min(Math.Max(this.updateDelay, 16), 2500);
+				this.updateDelayStr = ARConfiguration.UpdateDelay.ToString();
+			}
 
 			if (requireLineOfSight)
 			{
@@ -243,7 +381,7 @@
 				if (newRatio != graceRatio)
 				{
 					ARConfiguration.RadiusRatio = (1d - newRatio) * (1d - newRatio);
-					this.SaveConfigValue("graceRatio", newRatio);
+					this.SaveConfigValue(GRACE_RATIO_KEY, newRatio);
 				}
 
 				GUILayout.EndHorizontal();
@@ -257,19 +395,22 @@
 		public void OnDestroy()
 		{
 			GameEvents.onGameSceneLoadRequested.Remove(this.onSceneChangeRequested);
+			GameEvents.OnKSCFacilityUpgraded.Remove(this.onFacilityUpgraded);
 
 			if (this.toolbarButton != null)
 			{
 				this.toolbarButton.Destroy();
+				this.toolbarButton = null;
 			}
 
 			if (this.appLauncherButton != null)
 			{
 				ApplicationLauncher.Instance.RemoveModApplication(this.appLauncherButton);
-			}
-		}
-
-		protected void onSceneChangeRequested(GameScenes scene)
+				this.appLauncherButton = null;
+			}
+		}
+
+		private void onSceneChangeRequested(GameScenes scene)
 		{
 			if (scene != GameScenes.SPACECENTER)
 			{
@@ -278,9 +419,46 @@
 			}
 		}
 
+		private void onFacilityUpgraded(Upgradeables.UpgradeableFacility fac, int lvl)
+		{
+			if (fac.id == "SpaceCenter/TrackingStation")
+			{
+				this.Log("Caught onFacilityUpgraded for {0} at level {1}", fac.id, lvl);
+				this.SetKerbinRelayRange();
+			}
+		}
+
+		private void SetKerbinRelayRange()
+		{
+			int tsLevel;
+
+			if (HighLogic.CurrentGame.Mode == Game.Modes.CAREER)
+			{
+				tsLevel = ScenarioUpgradeableFacilities.protoUpgradeables["SpaceCenter/TrackingStation"]
+					.facilityRefs[0].FacilityLevel;
+			
+
+			}
+			else
+			{
+				tsLevel = this.trackingStationRanges.Length - 1;
+			}
+
+			if (tsLevel < this.trackingStationRanges.Length && tsLevel >= 0)
+			{
+				KerbinRelayRange = this.trackingStationRanges[tsLevel];
+				this.Log("Setting Kerbin's range to {0}", KerbinRelayRange);
+			}
+			else
+			{
+				this.LogError("Could not set Kerbin's range with invalid Tracking Station level {0}", tsLevel);
+			}
+		}
+
 		private void toggleConfigWindow()
 		{
 			this.showConfigWindow = !this.showConfigWindow;
+			this.updateDelayStr = ARConfiguration.UpdateDelay.ToString();
 		}
 
 		private T LoadConfigValue<T>(string key, T defaultValue)

--- a/ARFlightController.cs
+++ b/ARFlightController.cs
@@ -2,7 +2,7 @@
 //
 // ARFlightController.cs
 //
-// Copyright © 2014, toadicus
+// Copyright © 2014-2015, toadicus
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without modification,
@@ -39,8 +39,13 @@
 	[KSPAddon(KSPAddon.Startup.Flight, false)]
 	public class ARFlightController : MonoBehaviour
 	{
+		#region Static
+		private static List<IAntennaRelay> usefulRelays;
+		public static IList<IAntennaRelay> UsefulRelays;
+		#endregion
+
 		#region Fields
-		private Dictionary<ConnectionStatus, string> connectionTextures;
+		private Dictionary<ConnectionStatus, string> toolbarTextures;
 		private Dictionary<ConnectionStatus, Texture> appLauncherTextures;
 
 		private ARMapRenderer mapRenderer;
@@ -64,7 +69,7 @@
 		{
 			get
 			{
-				return this.connectionTextures[this.currentConnectionStatus];
+				return this.toolbarTextures[this.currentConnectionStatus];
 			}
 		}
 
@@ -126,11 +131,11 @@
 
 			this.updateTimer = new System.Diagnostics.Stopwatch();
 
-			this.connectionTextures = new Dictionary<ConnectionStatus, string>();
-
-			this.connectionTextures[ConnectionStatus.None] = "AntennaRange/Textures/toolbarIconNoConnection";
-			this.connectionTextures[ConnectionStatus.Suboptimal] = "AntennaRange/Textures/toolbarIconSubOptimal";
-			this.connectionTextures[ConnectionStatus.Optimal] = "AntennaRange/Textures/toolbarIcon";
+			this.toolbarTextures = new Dictionary<ConnectionStatus, string>();
+
+			this.toolbarTextures[ConnectionStatus.None] = "AntennaRange/Textures/toolbarIconNoConnection";
+			this.toolbarTextures[ConnectionStatus.Suboptimal] = "AntennaRange/Textures/toolbarIconSubOptimal";
+			this.toolbarTextures[ConnectionStatus.Optimal] = "AntennaRange/Textures/toolbarIcon";
 
 			this.appLauncherTextures = new Dictionary<ConnectionStatus, Texture>();
 
@@ -145,31 +150,21 @@
 			{
 				this.toolbarButton = ToolbarManager.Instance.add("AntennaRange", "ARConnectionStatus");
 
-				this.toolbarButton.TexturePath = this.connectionTextures[ConnectionStatus.None];
+				this.toolbarButton.TexturePath = this.toolbarTextures[ConnectionStatus.None];
 				this.toolbarButton.Text = "AntennaRange";
 				this.toolbarButton.Visibility = new GameScenesVisibility(GameScenes.FLIGHT);
-				this.toolbarButton.Enabled = false;
+				this.toolbarButton.OnClick += (e) => (this.buttonToggle());
 			}
 
 			GameEvents.onGameSceneLoadRequested.Add(this.onSceneChangeRequested);
 			GameEvents.onVesselChange.Add(this.onVesselChange);
-		}
-
-		private void Start()
-		{
-			this.mapRenderer = MapView.MapCamera.gameObject.AddComponent<ARMapRenderer>();
+
+			usefulRelays = new List<IAntennaRelay>();
+			UsefulRelays = usefulRelays.AsReadOnly();
 		}
 
 		private void FixedUpdate()
 		{
-			if (this.appLauncherButton == null && !ToolbarManager.ToolbarAvailable && ApplicationLauncher.Ready)
-			{
-				this.appLauncherButton = ApplicationLauncher.Instance.AddModApplication(
-					ApplicationLauncher.AppScenes.FLIGHT | ApplicationLauncher.AppScenes.MAPVIEW,
-					this.appLauncherTextures[ConnectionStatus.None]
-				);
-			}
-
 			this.log.Clear();
 
 			VesselCommand availableCommand;
@@ -224,7 +219,26 @@
 
 		private void Update()
 		{
-			if (!this.updateTimer.IsRunning || this.updateTimer.ElapsedMilliseconds > 83L)
+			if (MapView.MapIsEnabled && this.mapRenderer == null)
+			{
+				this.mapRenderer = MapView.MapCamera.gameObject.AddComponent<ARMapRenderer>();
+			}
+
+			if (this.toolbarButton != null)
+			{
+				this.toolbarButton.Enabled = MapView.MapIsEnabled;
+			}
+
+			if (this.appLauncherButton == null && !ToolbarManager.ToolbarAvailable && ApplicationLauncher.Ready)
+			{
+				this.appLauncherButton = ApplicationLauncher.Instance.AddModApplication(
+					this.buttonToggle, this.buttonToggle,
+					ApplicationLauncher.AppScenes.FLIGHT | ApplicationLauncher.AppScenes.MAPVIEW,
+					this.appLauncherTextures[ConnectionStatus.None]
+				);
+			}
+
+			if (!this.updateTimer.IsRunning || this.updateTimer.ElapsedMilliseconds > ARConfiguration.UpdateDelay)
 			{
 				this.updateTimer.Restart();
 			}
@@ -235,11 +249,13 @@
 
 			this.log.Clear();
 
-			if (HighLogic.LoadedSceneIsFlight && FlightGlobals.ActiveVessel != null)
+			if (HighLogic.LoadedSceneIsFlight && FlightGlobals.ready && FlightGlobals.ActiveVessel != null)
 			{
 				Vessel vessel;
 				IAntennaRelay relay;
 				IList<IAntennaRelay> activeVesselRelays;
+
+				usefulRelays.Clear();
 
 				for (int vIdx = 0; vIdx < FlightGlobals.Vessels.Count; vIdx++)
 				{
@@ -258,6 +274,7 @@
 					{
 						log.AppendFormat("Finding nearest relay for best relay {0}", relay);
 
+						usefulRelays.Add(relay);
 						relay.FindNearestRelay();
 					}
 				}
@@ -269,6 +286,8 @@
 
 					relay.FindNearestRelay();
 				}
+
+				usefulRelays.Add(RelayDatabase.Instance.GetBestVesselRelay(FlightGlobals.ActiveVessel));
 
 				if (this.toolbarButton != null || this.appLauncherButton != null)
 				{
@@ -329,6 +348,14 @@
 		}
 		#endregion
 
+		private void buttonToggle()
+		{
+			if (MapView.MapIsEnabled)
+			{
+				ARConfiguration.PrettyLines = !ARConfiguration.PrettyLines;
+			}
+		}
+
 		#region Event Handlers
 		private void onSceneChangeRequested(GameScenes scene)
 		{

--- a/ARMapRenderer.cs
+++ b/ARMapRenderer.cs
@@ -2,7 +2,7 @@
 //
 // ARMapRenderer.cs
 //
-// Copyright © 2014, toadicus
+// Copyright © 2014-2015, toadicus
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without modification,
@@ -38,6 +38,13 @@
 {
 	public class ARMapRenderer : MonoBehaviour
 	{
+		#if BENCH
+		private static ulong updateCount = 0u;
+		private static ulong updateTimer = 0u;
+		private readonly static RollingAverage averager = new RollingAverage();
+		private static long twiceAverageTime = long.MaxValue;
+		#endif
+
 		#region Fields
 		private Dictionary<Guid, LineRenderer> vesselLineRenderers;
 
@@ -59,18 +66,9 @@
 		{
 			get
 			{
-				if (this.vesselLineRenderers == null)
-				{
-					this.vesselLineRenderers = new Dictionary<Guid, LineRenderer>();
-				}
-
 				LineRenderer lr;
 
-				if (this.vesselLineRenderers.TryGetValue(idx, out lr))
-				{
-					return lr;
-				}
-				else
+				if (!this.vesselLineRenderers.TryGetValue(idx, out lr))
 				{
 					GameObject obj = new GameObject();
 					obj.layer = 31;
@@ -85,6 +83,8 @@
 
 					return lr;
 				}
+
+				return lr;
 			}
 		}
 		#endregion
@@ -97,8 +97,10 @@
 				this.vesselLineRenderers = new Dictionary<Guid, LineRenderer>();
 			}
 
+			#if DEBUG || BENCH
+			this.timer = new System.Diagnostics.Stopwatch();
+			#endif
 			#if DEBUG
-			this.timer = new System.Diagnostics.Stopwatch();
 			this.log = Tools.DebugLogger.New(this);
 			#endif
 		}
@@ -107,12 +109,12 @@
 		{
 			if (!HighLogic.LoadedSceneIsFlight || !MapView.MapIsEnabled || !ARConfiguration.PrettyLines)
 			{
-				this.Cleanup();
+				this.Cleanup(!HighLogic.LoadedSceneIsFlight);
 
 				return;
 			}
 
-			#if DEBUG
+			#if DEBUG || BENCH
 			timer.Restart();
 			#endif
 
@@ -130,67 +132,36 @@
 					MapView.MapCamera.Distance
 				);
 
-				if (FlightGlobals.ready && FlightGlobals.Vessels != null)
-				{
-					log.AppendLine("FlightGlobals ready and Vessels list not null.");
-
-					for (int i = 0; i < FlightGlobals.Vessels.Count; i++)
+				log.AppendLine("FlightGlobals ready and Vessels list not null.");
+
+				IAntennaRelay relay;
+
+				for (int i = 0; i < ARFlightController.UsefulRelays.Count; i++)
+				{
+					relay = ARFlightController.UsefulRelays[i];
+
+					if (relay == null)
 					{
-						Vessel vessel = FlightGlobals.Vessels[i];
-
-						log.AppendFormat("\nStarting check for vessel {0} at {1}ms", vessel, timer.ElapsedMilliseconds);
-
-						if (vessel == null)
-						{
-							log.AppendFormat("\n\tSkipping vessel {0} altogether because it is null.", vessel);
-							continue;
-						}
-
-						switch (vessel.vesselType)
-						{
-							case VesselType.Debris:
-							case VesselType.EVA:
-							case VesselType.Unknown:
-							case VesselType.SpaceObject:
-								log.AppendFormat("\n\tDiscarded because vessel is of invalid type {0}",
-									vessel.vesselType);
-								continue;
-						}
-
-						log.AppendFormat("\n\tChecking vessel {0}.", vessel.vesselName);
-
-						#if DEBUG
-						start = timer.ElapsedMilliseconds;
-						#endif
-
-						IAntennaRelay vesselRelay = vessel.GetBestRelay();
-
-						if (vesselRelay == null)
-						{
-							continue;
-						}
-
-						log.AppendFormat("\n\tGot best relay {0} ({3}) for vessel {1} in {2} ms",
-							vesselRelay, vessel, timer.ElapsedMilliseconds - start, vesselRelay.GetType().Name);
-
-						if (vesselRelay != null)
-						{
-							#if DEBUG
-							start = timer.ElapsedMilliseconds;
-							#endif
-
-							this.SetRelayVertices(vesselRelay);
-
-							log.AppendFormat("\n\tSet relay vertices for {0} in {1}ms",
-								vessel, timer.ElapsedMilliseconds - start);
-						}
+						log.AppendFormat("\n\tGot null relay, skipping");
+						continue;
 					}
+
+					log.AppendFormat("\n\tDrawing pretty lines for useful relay {0}", relay);
+					
+					#if DEBUG
+					start = timer.ElapsedMilliseconds;
+					#endif
+
+					this.SetRelayVertices(relay);
+
+					log.AppendFormat("\n\tSet relay vertices for {0} in {1}ms",
+						relay, timer.ElapsedMilliseconds - start);
 				}
 			}
 			catch (Exception ex)
 			{
 				this.LogError("Caught {0}: {1}\n{2}\n", ex.GetType().Name, ex.ToString(), ex.StackTrace.ToString());
-				this.Cleanup();
+				this.Cleanup(false);
 			}
 			#if DEBUG
 			finally
@@ -200,13 +171,34 @@
 				log.Print();
 			}
 			#endif
+
+			#if BENCH
+			ARMapRenderer.updateCount++;
+			ARMapRenderer.updateTimer += (ulong)this.timer.ElapsedTicks;
+
+			if (ARMapRenderer.updateCount >= (ulong)(8d / Time.smoothDeltaTime))
+			{
+				ARMapRenderer.averager.AddItem((double)ARMapRenderer.updateTimer / (double)ARMapRenderer.updateCount);
+				ARMapRenderer.updateTimer = 0u;
+				ARMapRenderer.updateCount = 0u;
+				ARMapRenderer.twiceAverageTime = (long)(ARMapRenderer.averager.Average * 2d);
+			}
+
+			if (this.timer.ElapsedTicks > ARMapRenderer.twiceAverageTime)
+			{
+				this.Log("PreCull took significant longer than usual ({0:S3}s vs {1:S3}s)",
+					(double)this.timer.ElapsedTicks / (double)System.Diagnostics.Stopwatch.Frequency,
+					ARMapRenderer.averager.Average / (double)System.Diagnostics.Stopwatch.Frequency
+				);
+			}
+			#endif
 		}
 
 		private void OnDestroy()
 		{
-			this.Cleanup();
-
-			print("ARMapRenderer: Destroyed.");
+			this.Cleanup(true);
+
+			this.Log("Destroyed");
 		}
 		#endregion
 
@@ -260,7 +252,7 @@
 			}
 			else
 			{
-				if (relay.transmitDistance < relay.nominalTransmitDistance)
+				if (relay.LinkStatus == ConnectionStatus.Optimal)
 				{
 					thisColor = Color.green;
 				}
@@ -273,18 +265,21 @@
 			if (relay.KerbinDirect)
 			{
 				nextPoint = ScaledSpace.LocalToScaledSpace(AntennaRelay.Kerbin.position);
-				relay = null;
 			}
 			else
 			{
-				if (relay.targetRelay == null)
-				{
+				if (relay.targetRelay == null || relay.targetRelay.vessel == null)
+				{
+					this.LogError(
+						"SetRelayVertices: relay {0} has null target relay or vessel when not KerbinDirect, bailing out!",
+						relay
+					);
+
 					renderer.enabled = false;
 					return;
 				}
 
 				nextPoint = ScaledSpace.LocalToScaledSpace(relay.targetRelay.vessel.GetWorldPos3D());
-				relay = relay.targetRelay;
 			}
 
 			renderer.SetColors(thisColor, thisColor);
@@ -303,7 +298,7 @@
 			log.AppendFormat("\n\t\t\t...finished segment in {0} ms", timer.ElapsedMilliseconds - relayStart);
 		}
 
-		private void Cleanup()
+		private void Cleanup(bool freeObjects)
 		{
 			if (this.vesselLineRenderers != null && this.vesselLineRenderers.Count > 0)
 			{
@@ -314,9 +309,17 @@
 				{
 					lineRenderer = enumerator.Current;
 					lineRenderer.enabled = false;
-					GameObject.Destroy(lineRenderer.gameObject);
-				}
-				this.vesselLineRenderers.Clear();
+
+					if (freeObjects)
+					{
+						GameObject.Destroy(lineRenderer.gameObject);
+					}
+				}
+
+				if (freeObjects)
+				{
+					this.vesselLineRenderers.Clear();
+				}
 			}
 		}
 		#endregion

--- a/AntennaRelay.cs
+++ b/AntennaRelay.cs
@@ -2,7 +2,7 @@
 //
 // AntennaRelay.cs
 //
-// Copyright © 2014, toadicus
+// Copyright © 2014-2015, toadicus
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without modification,
@@ -37,9 +37,6 @@
 	/// </summary>
 	public class AntennaRelay
 	{
-		private static readonly System.Diagnostics.Stopwatch searchTimer = new System.Diagnostics.Stopwatch();
-		private const long millisecondsBetweenSearches = 125L;
-
 		// We don't have a Bard, so we'll hide Kerbin here.
 		private static CelestialBody _Kerbin;
 
@@ -59,10 +56,18 @@
 			}
 		}
 
-		private long lastSearch;
+		#if BENCH
+		private static ushort relayCount = 0;
+		private static ulong searchCount = 0u;
+		private static ulong searchTimer = 0u;
+		private readonly static RollingAverage averager = new RollingAverage(16);
+		private static long doubleAverageTime = long.MaxValue;
+
+
+		private System.Diagnostics.Stopwatch performanceTimer = new System.Diagnostics.Stopwatch();
+		#endif
 
 		private bool canTransmit;
-		private bool isChecked;
 
 		private IAntennaRelay nearestRelay;
 		private IAntennaRelay bestOccludedRelay;
@@ -95,31 +100,68 @@
 		}
 
 		/// <summary>
-		/// Gets the first <see cref="CelestialBody"/> found to be blocking line of sight.
-		/// </summary>
-		public virtual CelestialBody firstOccludingBody
+		/// Gets a value indicating whether this <see cref="AntennaRange.IAntennaRelay"/> Relay is communicating
+		/// directly with Kerbin.
+		/// </summary>
+		public virtual bool KerbinDirect
 		{
 			get;
 			protected set;
 		}
 
 		/// <summary>
+		/// Gets or sets the nominal link distance, in meters.
+		/// </summary>
+		public virtual double NominalLinkSqrDistance
+		{
+			get;
+			protected set;
+		}
+
+		/// <summary>
+		/// Gets or sets the maximum link distance, in meters.
+		/// </summary>
+		public virtual double MaximumLinkSqrDistance
+		{
+			get;
+			protected set;
+		}
+
+		/// <summary>
+		/// Gets the first <see cref="CelestialBody"/> found to be blocking line of sight.
+		/// </summary>
+		public virtual CelestialBody firstOccludingBody
+		{
+			get;
+			protected set;
+		}
+
+		/// <summary>
 		/// Gets the transmit distance.
 		/// </summary>
 		/// <value>The transmit distance.</value>
-		public double transmitDistance
+		public double CurrentLinkSqrDistance
 		{
 			get
 			{
 				if (this.KerbinDirect || this.targetRelay == null)
 				{
-					return this.DistanceTo(Kerbin);
+					return this.SqrDistanceTo(Kerbin);
 				}
 				else
 				{
-					return this.DistanceTo(this.targetRelay);
-				}
-			}
+					return this.SqrDistanceTo(this.targetRelay);
+				}
+			}
+		}
+
+		/// <summary>
+		/// Gets or sets the link status.
+		/// </summary>
+		public virtual ConnectionStatus LinkStatus
+		{
+			get;
+			protected set;
 		}
 
 		/// <summary>
@@ -142,16 +184,6 @@
 		}
 
 		/// <summary>
-		/// Gets a value indicating whether this <see cref="AntennaRange.IAntennaRelay"/> Relay is communicating
-		/// directly with Kerbin.
-		/// </summary>
-		public virtual bool KerbinDirect
-		{
-			get;
-			protected set;
-		}
-
-		/// <summary>
 		/// Determines whether this instance can transmit.
 		/// </summary>
 		/// <returns><c>true</c> if this instance can transmit; otherwise, <c>false</c>.</returns>
@@ -169,11 +201,6 @@
 			if (!FlightGlobals.ready)
 			{
 				return;
-			}
-
-			if (!searchTimer.IsRunning)
-			{
-				searchTimer.Start();
 			}
 
 			Tools.DebugLogger log;
@@ -181,38 +208,51 @@
 			log = Tools.DebugLogger.New(this);
 			#endif
 
-			long searchTime = searchTimer.ElapsedMilliseconds;
-			long timeSinceLast = searchTime - this.lastSearch;
-
-			if (timeSinceLast < millisecondsBetweenSearches)
-			{
-				log.AppendFormat(
-					"{0}: Target search skipped because it's not time to search again yet ({1} - {2}) < {3})",
-					this, searchTime, this.lastSearch, millisecondsBetweenSearches
-				);
-				log.Print();
-				return;
-			}
-
-			// Skip vessels that have already been checked for a nearest relay this pass.
-			if (this.isChecked)
-			{
-				log.AppendFormat("{0}: Target search skipped because our vessel has been checked already this search.",
-					this);
-				log.Print();
-				return;
-			}
-
-			log.AppendFormat("{0}: Target search started at {1} ms ({2} ms since last search).",
-				this.ToString(), searchTime, timeSinceLast);
+			#if BENCH
+			this.performanceTimer.Restart();
+
+			long startVesselLoopTicks;
+			long totalVesselLoopTicks;
+
+			string slowestLOSVesselName = string.Empty;
+			long slowestLOSVesselTicks = long.MinValue;
+			long startLOSVesselTicks;
+			long totalLOSVesselTicks;
+
+			string slowestCircularVesselName = string.Empty;
+			long slowestCircularVesselTicks = long.MinValue;
+			long startCircularVesselTicks;
+			long totalCircularVesselTicks;
+
+			long startKerbinLOSTicks;
+			long totalKerbinLOSTicks;
+			long statusResolutionTicks;
+
+			ushort usefulVesselCount = 0;
+			#endif
+
+			log.AppendFormat("{0}: Target search started).", this.ToString());
 
 			#if DEBUG
 			try {
 			#endif
-			// Set this vessel as checked, so that we don't check it again.
-			this.isChecked = true;
-
-			this.lastSearch = searchTime;
+
+			// Declare a bunch of variables we'll be using.
+			CelestialBody bodyOccludingBestOccludedRelay = null;
+			IAntennaRelay needle;
+
+			double nearestRelaySqrQuotient = double.PositiveInfinity;
+			double bestOccludedSqrQuotient = double.PositiveInfinity;
+
+			double potentialSqrDistance;
+			double maxLinkSqrDistance;
+			double potentialSqrQuotient;
+
+			double kerbinSqrDistance;
+			double kerbinSqrQuotient;
+
+			bool isCircular;
+			int iterCount;
 
 			// Blank everything we're trying to find before the search.
 			this.firstOccludingBody = null;
@@ -222,12 +262,6 @@
 
 			// Default to KerbinDirect = true in case something in here doesn't work right.
 			this.KerbinDirect = true;
-
-			CelestialBody bodyOccludingBestOccludedRelay = null;
-
-			double nearestRelaySqrDistance = double.PositiveInfinity;
-			double bestOccludedSqrDistance = double.PositiveInfinity;
-			double maxTransmitSqrDistance = this.maxTransmitDistance * this.maxTransmitDistance;
 
 			/*
 			 * Loop through all the vessels and exclude this vessel, vessels of the wrong type, and vessels that are too
@@ -235,195 +269,275 @@
 			 * and that can transmit.  Once we find a suitable candidate, assign it to nearestRelay for comparison
 			 * against future finds.
 			 * */
-			Vessel potentialVessel;
-			IList<IAntennaRelay> vesselRelays;
-			for (int vIdx = 0; vIdx < FlightGlobals.Vessels.Count; vIdx++)
-			{
-				log.AppendFormat("\nFetching vessel at index {0}", vIdx);
-				potentialVessel = FlightGlobals.Vessels[vIdx];
-				
-				if (potentialVessel == null)
-				{
-					log.AppendFormat("\n\tSkipping vessel at index {0} because it is null.", vIdx);
-					log.Print();
-					return;
-				}
-				#if DEBUG
-				else
-				{
-					log.AppendFormat("\n\tGot vessel {0}", potentialVessel);
-				}
+			// Vessel potentialVessel;
+			IAntennaRelay potentialBestRelay;
+			CelestialBody fob;
+
+			#if BENCH
+			startVesselLoopTicks = performanceTimer.ElapsedTicks;
+			#endif
+
+			for (int rIdx = 0; rIdx < ARFlightController.UsefulRelays.Count; rIdx++)
+			{
+				potentialBestRelay = ARFlightController.UsefulRelays[rIdx];
+				log.AppendFormat("\n\t\tgot best vessel relay {0}",
+					potentialBestRelay == null ? "null" : potentialBestRelay.ToString());
+
+				if (potentialBestRelay == null)
+				{
+					log.Append("\n\t\t...skipping null relay");
+					continue;
+				}
+
+				if (potentialBestRelay == this || potentialBestRelay.vessel == this.vessel)
+				{
+					continue;
+				}
+
+				#if BENCH
+				usefulVesselCount++;
 				#endif
-
-				// Skip vessels of the wrong type.
-				log.Append("\n\tchecking vessel type");
-				switch (potentialVessel.vesselType)
-				{
-					case VesselType.Debris:
-					case VesselType.Flag:
-					case VesselType.EVA:
-					case VesselType.SpaceObject:
-					case VesselType.Unknown:
-							log.Append("\n\tSkipping because vessel is the wrong type.");
-						continue;
-					default:
-						break;
-				}
-				
-				log.Append("\n\tchecking if vessel is this vessel");
-				// Skip vessels with the wrong ID
-				if (potentialVessel.id == vessel.id)
-				{
-					log.Append("\n\tSkipping because vessel is this vessel.");
-					continue;
-				}
 
 				// Find the distance from here to the vessel...
 				log.Append("\n\tgetting distance to potential vessel");
-				double potentialSqrDistance = this.sqrDistanceTo(potentialVessel);
-				log.Append("\n\tgetting vessel relays");
-				vesselRelays = potentialVessel.GetAntennaRelays();
-					log.AppendFormat("\n\t\tvesselRelays: {0}",
-						vesselRelays == null ? "null" : vesselRelays.Count.ToString());
-
-				CelestialBody fob = null;
-				
-				log.Append("\n\tdoing LOS check");
+				potentialSqrDistance = this.SqrDistanceTo(potentialBestRelay);
+				log.Append("\n\tgetting best vessel relay");
+
+				log.Append("\n\tgetting max link distance to potential relay");
+
+				if (ARConfiguration.UseAdditiveRanges)
+				{
+					maxLinkSqrDistance = this.maxTransmitDistance * potentialBestRelay.maxTransmitDistance;
+				}
+				else
+				{
+					maxLinkSqrDistance = this.maxTransmitDistance * this.maxTransmitDistance;
+				}
+
+				log.AppendFormat("\n\tmax link distance: {0}", maxLinkSqrDistance);
+
+				potentialSqrQuotient = potentialSqrDistance / maxLinkSqrDistance;
+
+				#if BENCH
+				startLOSVesselTicks = performanceTimer.ElapsedTicks;
+				#endif
+
+				log.Append("\n\t\tdoing LOS check");
 				// Skip vessels to which we do not have line of sight.
 				if (
 					ARConfiguration.RequireLineOfSight &&
-					!this.vessel.hasLineOfSightTo(potentialVessel, out fob, ARConfiguration.RadiusRatio)
+					!this.vessel.hasLineOfSightTo(potentialBestRelay.vessel, out fob, ARConfiguration.RadiusRatio)
 				)
 				{
-					log.Append("\n\tfailed LOS check");
-					this.firstOccludingBody = fob;
+					#if BENCH
+					totalLOSVesselTicks = performanceTimer.ElapsedTicks - startLOSVesselTicks;
+
+					if (totalLOSVesselTicks > slowestLOSVesselTicks)
+					{
+						slowestLOSVesselTicks = totalLOSVesselTicks;
+						slowestLOSVesselName = vessel.vesselName;
+					}
+					#endif
+
+					log.Append("\n\t\t...failed LOS check");
+
+					log.AppendFormat("\n\t\t\t{0}: Relay {1} not in line of sight.",
+						this.ToString(), potentialBestRelay);
 					
-					log.AppendFormat("\n\t{0}: Vessel {1} not in line of sight.",
-						this.ToString(), potentialVessel.vesselName);
+					log.AppendFormat("\n\t\t\tpotentialSqrDistance: {0}", potentialSqrDistance);
+					log.AppendFormat("\n\t\t\tbestOccludedSqrQuotient: {0}", bestOccludedSqrQuotient);
+					log.AppendFormat("\n\t\t\tmaxTransmitSqrDistance: {0}", maxLinkSqrDistance);
+
+					if (
+						(potentialSqrQuotient < bestOccludedSqrQuotient) &&
+						(potentialSqrQuotient <= 1d) &&
+						potentialBestRelay.CanTransmit()
+					)
+					{
+						log.Append("\n\t\t...vessel is close enough to and potentialBestRelay can transmit");
+						log.AppendFormat("\n\t\t...{0} found new best occluded relay {1}", this, potentialBestRelay);
+
+						this.bestOccludedRelay = potentialBestRelay;
+						bodyOccludingBestOccludedRelay = fob;
+						bestOccludedSqrQuotient = potentialSqrQuotient;
+					}
+					else
+					{
+						log.Append("\n\t\t...vessel is not close enough to check for occluded relays, carrying on");
+					}
 					
-					log.AppendFormat("\n\t\tpotentialSqrDistance: {0}", potentialSqrDistance);
-					log.AppendFormat("\n\t\tbestOccludedSqrDistance: {0}", bestOccludedSqrDistance);
-					log.AppendFormat("\n\t\tmaxTransmitSqrDistance: {0}", maxTransmitSqrDistance);
-
-					if (
-						(potentialSqrDistance < bestOccludedSqrDistance) &&
-						(potentialSqrDistance < maxTransmitSqrDistance)
-					)
-					{
-						log.Append("\n\t\t...vessel is close enough to check for occluded relays");
-						log.AppendFormat("\n\t\tthis: {0}", this);
-						log.AppendFormat("\n\t\tpotentialVessel: {0}",
-							potentialVessel == null ? "null" : potentialVessel.ToString());
-						log.AppendFormat("\n\t\tvesselRelays: {0}",
-							vesselRelays == null ? "null" : vesselRelays.ToString());
-
-						log.AppendFormat("\n\t\t{0}: Checking {1} relays on occluded vessel {2}.",
-							this.ToString(),
-							vesselRelays.Count,
-							potentialVessel
-						);
-
-						IAntennaRelay occludedRelay;
-						for (int rIdx = 0; rIdx < vesselRelays.Count; rIdx++)
-						{
-							occludedRelay = vesselRelays[rIdx];
-
-							log.AppendFormat(
-								"\n\t\t{0}: Checking candidate for bestOccludedRelay: {1}" +
-								"\n\t\tCanTransmit: {2}",
-								this.ToString(), occludedRelay, occludedRelay.CanTransmit()
-							);
-							
-							if (occludedRelay.CanTransmit())
-							{
-								this.bestOccludedRelay = occludedRelay;
-								bodyOccludingBestOccludedRelay = fob;
-								bestOccludedSqrDistance = potentialSqrDistance;
-
-								log.AppendFormat("\n\t{0}: Found new bestOccludedRelay: {1}" +
-									" (blocked by {2}; distance: {3} m)",
-									this.ToString(),
-									occludedRelay.ToString(),
-									fob,
-									potentialSqrDistance
-								);
-								break;
-							}
-						}
-					}
-					
-					log.Append("\n\t\t...vessel is not close enough to check for occluded relays, carrying on");
 					continue;
 				}
-
-				log.Append("\n\tpassed LOS check");
+				#if BENCH
+				else
+				{
+					totalLOSVesselTicks = performanceTimer.ElapsedTicks - startLOSVesselTicks;
+				}
+
+				if (totalLOSVesselTicks > slowestLOSVesselTicks)
+				{
+					slowestLOSVesselTicks = totalLOSVesselTicks;
+					slowestLOSVesselName = vessel.vesselName;
+				}
+				#endif
+
+				log.Append("\n\t\t...passed LOS check");
 
 				/*
 				 * ...so that we can skip the vessel if it is further away than a vessel we've already checked.
 				 * */
-				if (potentialSqrDistance > nearestRelaySqrDistance)
+				if (potentialSqrQuotient > nearestRelaySqrQuotient)
 				{
 					
-					log.AppendFormat("\n\t{0}: Vessel {1} discarded because it is farther than another the nearest relay.",
+					log.AppendFormat("\n\t{0}: Relay {1} discarded because it is farther than another the nearest relay.",
 						this.ToString(),
-						potentialVessel.vesselName
+						potentialBestRelay
 					);
 					continue;
 				}
 
-				log.Append("\n\tpassed distance check");
-
-				IAntennaRelay potentialRelay;
-				for (int rIdx = 0; rIdx < vesselRelays.Count; rIdx++)
-				{
-					log.AppendFormat("\n\t\tfetching vessel relay at index {0}", rIdx);
-					potentialRelay = vesselRelays[rIdx];
-					log.AppendFormat("\n\t\tgot relay {0}", potentialRelay == null ? "null" : potentialRelay.ToString());
-
-					if (potentialRelay == null)
-					{
-						log.Append("\n\t\t...skipping null relay");
-						continue;
-					}
-
-					if (
-						potentialRelay.CanTransmit() &&
-						(potentialRelay.targetRelay == null || potentialRelay.targetRelay.vessel != this.vessel))
-					{
-						// @TODO: Moved this here from outside the loop; why was it there?
-						nearestRelaySqrDistance = potentialSqrDistance;
-						this.nearestRelay = potentialRelay;
-
-						log.AppendFormat("\n\t{0}: found new nearest relay {1} ({2}m)",
+				log.Append("\n\t\t...passed distance check");
+
+				if (potentialBestRelay.CanTransmit())
+				{
+					#if BENCH
+					startCircularVesselTicks = performanceTimer.ElapsedTicks;
+					#endif
+
+					needle = potentialBestRelay;
+					isCircular = false;
+
+					iterCount = 0;
+					while (needle != null)
+					{
+						iterCount++;
+
+						if (needle.KerbinDirect)
+						{
+							break;
+						}
+
+						if (needle.targetRelay == null)
+						{
+							break;
+						}
+
+						if (needle.targetRelay.vessel == this.vessel || needle == this.moduleRef)
+						{
+							isCircular = true;
+							break;
+						}
+
+						// Avoid infinite loops when we're not catching things right.
+						if (iterCount > FlightGlobals.Vessels.Count)
+						{
+							Tools.PostErrorMessage(
+								"[{0}] iterCount exceeded while checking for circular network; assuming it is circular" +
+								"\n\tneedle={1}" +
+								"\n\tthis.moduleRef={2}",
+								this,
+								needle == null ? "null" : string.Format(
+									"{0}, needle.KerbinDirect={1}, needle.targetRelay={2}",
+									needle, needle.KerbinDirect, needle.targetRelay == null ? "null" : string.Format(
+										"{0}\n\tneedle.targetRelay.vessel={1}",
+										needle.targetRelay,
+										needle.targetRelay.vessel == null ?
+											"null" : needle.targetRelay.vessel.vesselName
+									)
+								),
+								this.moduleRef == null ? "null" : this.moduleRef.ToString()
+							);
+							isCircular = true;
+							break;
+						}
+
+						needle = needle.targetRelay;
+					}
+
+					if (!isCircular)
+					{
+						nearestRelaySqrQuotient = potentialSqrQuotient;
+						this.nearestRelay = potentialBestRelay;
+
+						log.AppendFormat("\n\t{0}: found new nearest relay {1} ({2}m²)",
 							this.ToString(),
 							this.nearestRelay.ToString(),
-							Math.Sqrt(nearestRelaySqrDistance)
+							Math.Sqrt(nearestRelaySqrQuotient)
 						);
-						
-						break;
-					}
-				}
-			}
+					}
+					else
+					{
+						log.AppendFormat("\n\t\t...connection to {0} would result in a circular network, skipping",
+							potentialBestRelay
+						);
+					}
+
+					#if BENCH
+					totalCircularVesselTicks = performanceTimer.ElapsedTicks - startCircularVesselTicks;
+
+					if (totalCircularVesselTicks > slowestCircularVesselTicks)
+					{
+						slowestCircularVesselName = vessel.vesselName;
+						slowestCircularVesselTicks = totalCircularVesselTicks;
+					}
+
+					#endif
+				}
+			}
+
+			#if BENCH
+			totalVesselLoopTicks = performanceTimer.ElapsedTicks - startVesselLoopTicks;
+			#endif
 
 			CelestialBody bodyOccludingKerbin = null;
 
-			double kerbinSqrDistance = this.vessel.DistanceTo(Kerbin) - Kerbin.Radius;
+			kerbinSqrDistance = this.vessel.DistanceTo(Kerbin) - Kerbin.Radius;
 			kerbinSqrDistance *= kerbinSqrDistance;
 
+			if (ARConfiguration.UseAdditiveRanges)
+			{
+				kerbinSqrQuotient = kerbinSqrDistance /
+					(this.maxTransmitDistance * ARConfiguration.KerbinRelayRange);
+			}
+			else
+			{
+				kerbinSqrQuotient = kerbinSqrDistance /
+					(this.maxTransmitDistance * this.maxTransmitDistance);
+			}
+
 			log.AppendFormat("\n{0} ({1}): Search done, figuring status.", this.ToString(), this.GetType().Name);
+			log.AppendFormat(
+				"\n{0}: nearestRelay={1} ({2}m²)), bestOccludedRelay={3} ({4}m²), kerbinSqrDistance={5}m²)",
+				this,
+				this.nearestRelay == null ? "null" : this.nearestRelay.ToString(),
+				nearestRelaySqrQuotient,
+				this.bestOccludedRelay == null ? "null" : this.bestOccludedRelay.ToString(),
+				bestOccludedSqrQuotient,
+				kerbinSqrDistance
+			);
+
+			#if BENCH
+			startKerbinLOSTicks = this.performanceTimer.ElapsedTicks;
+			#endif
 
 			// If we don't have LOS to Kerbin, focus on relays
-			if (!this.vessel.hasLineOfSightTo(Kerbin, out bodyOccludingKerbin, ARConfiguration.RadiusRatio))
-			{
+			if (
+				ARConfiguration.RequireLineOfSight &&
+				!this.vessel.hasLineOfSightTo(Kerbin, out bodyOccludingKerbin, ARConfiguration.RadiusRatio)
+			)
+			{
+				#if BENCH
+				totalKerbinLOSTicks = this.performanceTimer.ElapsedTicks - startKerbinLOSTicks;
+				#endif
 				log.AppendFormat("\n\tKerbin LOS is blocked by {0}.", bodyOccludingKerbin.bodyName);
 
 				// nearestRelaySqrDistance will be infinity if all relays are occluded or none exist.
 				// Therefore, this will only be true if a valid relay is in range.
-				if (nearestRelaySqrDistance <= maxTransmitSqrDistance)
+				if (nearestRelaySqrQuotient <= 1d)
 				{
 					log.AppendFormat("\n\t\tCan transmit to nearby relay {0} ({1} <= {2}).",
 						this.nearestRelay == null ? "null" : this.nearestRelay.ToString(),
-							nearestRelaySqrDistance, maxTransmitSqrDistance);
+						nearestRelaySqrQuotient, 1d);
 
 					this.KerbinDirect = false;
 					this.canTransmit = true;
@@ -434,13 +548,13 @@
 				{
 					log.AppendFormat("\n\t\tCan't transmit to nearby relay {0} ({1} > {2}).",
 						this.nearestRelay == null ? "null" : this.nearestRelay.ToString(),
-							nearestRelaySqrDistance, maxTransmitSqrDistance);
+						nearestRelaySqrQuotient, 1d);
 
 					this.canTransmit = false;
 
 					// If the best occluded relay is closer than Kerbin, check it against the nearest relay.
 					// Since bestOccludedSqrDistance is infinity if there are no occluded relays, this is safe
-					if (bestOccludedSqrDistance < kerbinSqrDistance)
+					if (bestOccludedSqrQuotient < kerbinSqrQuotient)
 					{
 						log.AppendFormat("\n\t\t\tBest occluded relay is closer than Kerbin ({0} < {1})",
 							bestOccludedRelay, kerbinSqrDistance);
@@ -449,19 +563,19 @@
 
 						// If the nearest relay is closer than the best occluded relay, pick it.
 						// Since nearestRelaySqrDistane is infinity if there are no nearby relays, this is safe.
-						if (nearestRelaySqrDistance < bestOccludedSqrDistance)
+						if (nearestRelaySqrQuotient < bestOccludedSqrQuotient)
 						{
 							log.AppendFormat("\n\t\t\t\t...but the nearest relay is closer ({0} < {1}), so picking it.",
-								nearestRelaySqrDistance, bestOccludedSqrDistance);
+								nearestRelaySqrQuotient, bestOccludedSqrQuotient);
 							
-							this.targetRelay = nearestRelay;
+							this.targetRelay = this.nearestRelay;
 							this.firstOccludingBody = null;
 						}
 						// Otherwise, target the best occluded relay.
 						else
 						{
 							log.AppendFormat("\n\t\t\t\t...and closer than the nearest relay ({0} >= {1}), so picking it.",
-								nearestRelaySqrDistance, bestOccludedSqrDistance);
+								nearestRelaySqrQuotient, bestOccludedSqrQuotient);
 							
 							this.targetRelay = bestOccludedRelay;
 							this.firstOccludingBody = bodyOccludingBestOccludedRelay;
@@ -474,25 +588,25 @@
 						log.AppendFormat("\n\t\t\tKerbin is closer than the best occluded relay ({0} >= {1})",
 							bestOccludedRelay, kerbinSqrDistance);
 						
-						this.firstOccludingBody = null;
-
 						// If the nearest relay is closer than Kerbin, pick it.
 						// Since nearestRelaySqrDistane is infinity if there are no nearby relays, this is safe.
-						if (nearestRelaySqrDistance < kerbinSqrDistance)
+						if (nearestRelaySqrQuotient < kerbinSqrQuotient)
 						{
 							log.AppendFormat("\n\t\t\t\t...but the nearest relay is closer ({0} < {1}), so picking it.",
-								nearestRelaySqrDistance, kerbinSqrDistance);
+								nearestRelaySqrQuotient, kerbinSqrQuotient);
 							
 							this.KerbinDirect = false;
-							this.targetRelay = nearestRelay;
+							this.firstOccludingBody = null;
+							this.targetRelay = this.nearestRelay;
 						}
 						// Otherwise, pick Kerbin.
 						else
 						{
 							log.AppendFormat("\n\t\t\t\t...and closer than the nearest relay ({0} >= {1}), so picking it.",
-								nearestRelaySqrDistance, kerbinSqrDistance);
+								nearestRelaySqrQuotient, kerbinSqrQuotient);
 							
 							this.KerbinDirect = true;
+							this.firstOccludingBody = bodyOccludingKerbin;
 							this.targetRelay = null;
 						}
 					}
@@ -501,23 +615,27 @@
 			// If we do have LOS to Kerbin, try to prefer the closest of nearestRelay and Kerbin
 			else
 			{
+				#if BENCH
+				totalKerbinLOSTicks = this.performanceTimer.ElapsedTicks - startKerbinLOSTicks;
+				#endif
+
 				log.AppendFormat("\n\tKerbin is in LOS.");
 
 				// If the nearest relay is closer than Kerbin and in range, transmit to it.
-				if (nearestRelaySqrDistance <= maxTransmitSqrDistance)
+				if (nearestRelaySqrQuotient <= 1d)
 				{
 					log.AppendFormat("\n\t\tCan transmit to nearby relay {0} ({1} <= {2}).",
 						this.nearestRelay == null ? "null" : this.nearestRelay.ToString(),
-							nearestRelaySqrDistance, maxTransmitSqrDistance);
+						nearestRelaySqrQuotient, 1d);
 
 					this.canTransmit = true;
 
 					// If the nearestRelay is closer than Kerbin, use it.
-					if (nearestRelaySqrDistance < kerbinSqrDistance)
+					if (nearestRelaySqrQuotient < kerbinSqrQuotient)
 					{
 						log.AppendFormat("\n\t\t\tPicking relay {0} over Kerbin ({1} < {2}).",
 							this.nearestRelay == null ? "null" : this.nearestRelay.ToString(),
-							nearestRelaySqrDistance, kerbinSqrDistance);
+							nearestRelaySqrQuotient, kerbinSqrQuotient);
 
 						this.KerbinDirect = false;
 						this.targetRelay = this.nearestRelay;
@@ -527,7 +645,7 @@
 					{
 						log.AppendFormat("\n\t\t\tBut picking Kerbin over nearby relay {0} ({1} >= {2}).",
 							this.nearestRelay == null ? "null" : this.nearestRelay.ToString(),
-								nearestRelaySqrDistance, kerbinSqrDistance);
+							nearestRelaySqrQuotient, kerbinSqrQuotient);
 
 						this.KerbinDirect = true;
 						this.targetRelay = null;
@@ -538,13 +656,13 @@
 				{
 					log.AppendFormat("\n\t\tCan't transmit to nearby relay {0} ({1} > {2}).",
 						this.nearestRelay == null ? "null" : this.nearestRelay.ToString(),
-							nearestRelaySqrDistance, maxTransmitSqrDistance);
+							nearestRelaySqrQuotient, 1d);
 
 					// If Kerbin is in range, use it.
-					if (kerbinSqrDistance <= maxTransmitSqrDistance)
+					if (kerbinSqrQuotient <= 1d)
 					{
 						log.AppendFormat("\n\t\t\tCan transmit to Kerbin ({0} <= {1}).",
-							kerbinSqrDistance, maxTransmitSqrDistance);
+							kerbinSqrQuotient, 1d);
 
 						this.canTransmit = true;
 						this.KerbinDirect = true;
@@ -555,13 +673,13 @@
 					else
 					{
 						log.AppendFormat("\n\t\t\tCan't transmit to Kerbin ({0} > {1}).",
-							kerbinSqrDistance, maxTransmitSqrDistance);
+								kerbinSqrQuotient, 1d);
 
 						this.canTransmit = false;
 
 						// If the best occluded relay is closer than Kerbin, check it against the nearest relay.
 						// Since bestOccludedSqrDistance is infinity if there are no occluded relays, this is safe
-						if (bestOccludedSqrDistance < kerbinSqrDistance)
+						if (bestOccludedSqrQuotient < kerbinSqrQuotient)
 						{
 							log.AppendFormat("\n\t\t\tBest occluded relay is closer than Kerbin ({0} < {1})",
 								bestOccludedRelay, kerbinSqrDistance);
@@ -570,19 +688,19 @@
 
 							// If the nearest relay is closer than the best occluded relay, pick it.
 							// Since nearestRelaySqrDistane is infinity if there are no nearby relays, this is safe.
-							if (nearestRelaySqrDistance < bestOccludedSqrDistance)
+							if (nearestRelaySqrQuotient < bestOccludedSqrQuotient)
 							{
 								log.AppendFormat("\n\t\t\t\t...but the nearest relay is closer ({0} < {1}), so picking it.",
-									nearestRelaySqrDistance, bestOccludedSqrDistance);
+									nearestRelaySqrQuotient, bestOccludedSqrQuotient);
 								
-								this.targetRelay = nearestRelay;
+								this.targetRelay = this.nearestRelay;
 								this.firstOccludingBody = null;
 							}
 							// Otherwise, target the best occluded relay.
 							else
 							{
 								log.AppendFormat("\n\t\t\t\t...and closer than the nearest relay ({0} >= {1}), so picking it.",
-									nearestRelaySqrDistance, bestOccludedSqrDistance);
+									nearestRelaySqrQuotient, bestOccludedSqrQuotient);
 								
 								this.targetRelay = bestOccludedRelay;
 								this.firstOccludingBody = bodyOccludingBestOccludedRelay;
@@ -599,19 +717,19 @@
 
 							// If the nearest relay is closer than Kerbin, pick it.
 							// Since nearestRelaySqrDistane is infinity if there are no nearby relays, this is safe.
-							if (nearestRelaySqrDistance < kerbinSqrDistance)
+							if (nearestRelaySqrQuotient < kerbinSqrQuotient)
 							{
 								log.AppendFormat("\n\t\t\t\t...but the nearest relay is closer ({0} < {1}), so picking it.",
-									nearestRelaySqrDistance, kerbinSqrDistance);
+									nearestRelaySqrQuotient, kerbinSqrQuotient);
 								
 								this.KerbinDirect = false;
-								this.targetRelay = nearestRelay;
+								this.targetRelay = this.nearestRelay;
 							}
 							// Otherwise, pick Kerbin.
 							else
 							{
 								log.AppendFormat("\n\t\t\t\t...and closer than the nearest relay ({0} >= {1}), so picking it.",
-									nearestRelaySqrDistance, kerbinSqrDistance);
+									nearestRelaySqrQuotient, kerbinSqrQuotient);
 								
 								this.KerbinDirect = true;
 								this.targetRelay = null;
@@ -621,10 +739,46 @@
 				}
 			}
 
-			log.AppendFormat("{0}: Target search completed at {1} ms ({2} ms elapsed).",
-				this.ToString(), searchTimer.ElapsedMilliseconds, searchTimer.ElapsedMilliseconds - searchTime);;
-
-			log.AppendFormat("\n{0}: Status determination complete.", this.ToString());
+			if (ARConfiguration.UseAdditiveRanges)
+			{
+				if (this.KerbinDirect)
+				{
+					this.NominalLinkSqrDistance = this.nominalTransmitDistance * ARConfiguration.KerbinNominalRange;
+					this.MaximumLinkSqrDistance = this.maxTransmitDistance * ARConfiguration.KerbinRelayRange;
+				}
+				else
+				{
+					this.NominalLinkSqrDistance = this.nominalTransmitDistance * this.targetRelay.nominalTransmitDistance;
+					this.MaximumLinkSqrDistance = this.maxTransmitDistance * this.targetRelay.maxTransmitDistance;
+				}
+			}
+			else
+			{
+				this.NominalLinkSqrDistance = this.nominalTransmitDistance * this.nominalTransmitDistance;
+				this.MaximumLinkSqrDistance = this.maxTransmitDistance * this.maxTransmitDistance;
+			}
+
+			if (this.canTransmit)
+			{
+				if (this.CurrentLinkSqrDistance < this.NominalLinkSqrDistance)
+				{
+					this.LinkStatus = ConnectionStatus.Optimal;
+				}
+				else
+				{
+					this.LinkStatus = ConnectionStatus.Suboptimal;
+				}
+			}
+			else
+			{
+				this.LinkStatus = ConnectionStatus.None;
+			}
+
+			#if BENCH
+			statusResolutionTicks = performanceTimer.ElapsedTicks - startKerbinLOSTicks - totalKerbinLOSTicks;
+			#endif
+
+			log.AppendFormat("\n{0}: Target search and status determination complete.", this.ToString());
 			
 			#if DEBUG
 			} catch (Exception ex) {
@@ -638,9 +792,69 @@
 			#if DEBUG
 			}
 			#endif
-			// Now that we're done with our recursive CanTransmit checks, flag this relay as not checked so it can be
-			// used next time.
-			this.isChecked = false;
+
+			#if BENCH
+			AntennaRelay.searchTimer += (ulong)this.performanceTimer.ElapsedTicks;
+			AntennaRelay.searchCount++;
+			this.performanceTimer.Stop();
+
+			double averageSearchTime = (double)AntennaRelay.searchTimer / (double)AntennaRelay.searchCount;
+
+			if (AntennaRelay.searchCount >= 8000u / (ulong)ARConfiguration.UpdateDelay)
+			{
+				AntennaRelay.searchCount = 0u;
+				AntennaRelay.searchTimer = 0u;
+
+				AntennaRelay.averager.AddItem(averageSearchTime);
+				AntennaRelay.doubleAverageTime = (long)(AntennaRelay.averager.Average * 2d);
+			}
+
+			if (this.performanceTimer.ElapsedTicks > AntennaRelay.doubleAverageTime)
+			{
+				System.Text.StringBuilder sb = Tools.GetStringBuilder();
+
+				sb.AppendFormat(Tools.SIFormatter, "[AntennaRelay] FindNearestRelay search for {0}" +
+					" took significantly longer than average ({1:S3}s vs {2:S3}s)",
+					this.ToString(),
+					(double)this.performanceTimer.ElapsedTicks / (double)System.Diagnostics.Stopwatch.Frequency,
+					(double)AntennaRelay.averager.Average / (double)System.Diagnostics.Stopwatch.Frequency
+				);
+
+				sb.AppendFormat(Tools.SIFormatter, "\n\tVessel loop time: {0:S3}s",
+					(double)totalVesselLoopTicks / (double)System.Diagnostics.Stopwatch.Frequency
+				);
+
+				sb.AppendFormat(Tools.SIFormatter, "\n\t\tAverage vessel time for each of {1} vessels: {0:S3}s",
+					(double)totalVesselLoopTicks / (double)System.Diagnostics.Stopwatch.Frequency /
+					(double)usefulVesselCount,
+					usefulVesselCount
+				);
+
+				sb.AppendFormat(Tools.SIFormatter, "\n\t\tSlowest vessel LOS check: {0:S3}s to {1}",
+					(double)slowestLOSVesselTicks / (double)System.Diagnostics.Stopwatch.Frequency,
+					slowestLOSVesselName
+				);
+
+				sb.AppendFormat(Tools.SIFormatter, "\n\t\tSlowest circular relay check: {0:S3}s for {1}",
+					(double)slowestCircularVesselTicks / (double)System.Diagnostics.Stopwatch.Frequency,
+					slowestCircularVesselName
+				);
+
+				sb.AppendFormat(Tools.SIFormatter, "\n\tKerbin LOS check: {0:S3}s",
+					(double)totalKerbinLOSTicks / (double)System.Diagnostics.Stopwatch.Frequency
+				);
+
+				sb.AppendFormat(Tools.SIFormatter, "\n\tStatus resolution check: {0:S3}s",
+					(double)statusResolutionTicks / (double)System.Diagnostics.Stopwatch.Frequency
+				);
+
+				// sb.AppendFormat(Tools.SIFormatter, "", start)
+
+				Tools.PostWarningMessage(sb.ToString());
+
+				Tools.PutStringBuilder(sb);
+			}
+			#endif
 		}
 
 		/// <summary>
@@ -664,7 +878,10 @@
 		public AntennaRelay(IAntennaRelay module)
 		{
 			this.moduleRef = module;
-			this.isChecked = false;
+
+			#if BENCH
+			AntennaRelay.relayCount++;
+			#endif
 
 			Tools.PostLogMessage("{0}: constructed {1}", this.GetType().Name, this.ToString());
 		}

--- a/GameData/AntennaRange/AntennaRange.cfg
+++ b/GameData/AntennaRange/AntennaRange.cfg
@@ -2,7 +2,7 @@
 //
 // AntennaRange.cfg
 //
-// Copyright © 2014, toadicus
+// Copyright © 2014-2015, toadicus
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without modification,
@@ -42,7 +42,8 @@
 	@MODULE[ModuleDataTransmitter]
 	{
 		@name = ModuleLimitedDataTransmitter
-		nominalRange = 1500000
+		nominalRange = 6364
+		simpleRange = 20500000
 		maxPowerFactor = 8
 		maxDataFactor = 4
 	}
@@ -63,9 +64,10 @@
 	@MODULE[ModuleDataTransmitter]
 	{
 		@name = ModuleLimitedDataTransmitter
-		nominalRange = 30000000
-		maxPowerFactor = 8
-		maxDataFactor = 4
+		nominalRange = 3500000000
+		simpleRange = 18000000000
+		maxPowerFactor = 4
+		maxDataFactor = 8
 	}
 
 	MODULE
@@ -84,9 +86,11 @@
 	@MODULE[ModuleDataTransmitter]
 	{
 		@name = ModuleLimitedDataTransmitter
-		nominalRange = 80000000000
-		maxPowerFactor = 8
-		maxDataFactor = 4
+		@packetResourceCost /= 1.414213
+		nominalRange = 10000000000
+		simpleRange = 56250000000
+		maxPowerFactor = 16
+		maxDataFactor = 2
 	}
 
 	MODULE
@@ -100,11 +104,18 @@
 	}
 }
 
+TRACKING_STATION_RANGES
+{
+	range = 800000
+	range = 200000000000
+	range = 2250000000000
+}
+
 EVA_MODULE
 {
 	name = ModuleLimitedDataTransmitter
 
-	nominalRange = 5000
+	nominalRange = 1389
 	maxPowerFactor = 1
 	maxDataFactor = 1
 

--- a/IAntennaRelay.cs
+++ b/IAntennaRelay.cs
@@ -2,7 +2,7 @@
 //
 // IAntennaRelay.cs
 //
-// Copyright © 2014, toadicus
+// Copyright © 2014-2015, toadicus
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without modification,
@@ -47,9 +47,31 @@
 		IAntennaRelay targetRelay { get; }
 
 		/// <summary>
+		/// Gets a value indicating whether this <see cref="AntennaRange.IAntennaRelay"/> Relay is communicating
+		/// directly with Kerbin.
+		/// </summary>
+		bool KerbinDirect { get; }
+
+		/// <summary>
+		/// The link distance, in meters, at which this relay behaves nominally.
+		/// </summary>
+		double NominalLinkSqrDistance { get; }
+
+
+		/// <summary>
+		/// The link distance, in meters, beyond which this relay cannot operate.
+		/// </summary>
+		double MaximumLinkSqrDistance { get; }
+
+		/// <summary>
 		/// Gets the distance to the nearest relay or Kerbin, whichever is closer.
 		/// </summary>
-		double transmitDistance { get; }
+		double CurrentLinkSqrDistance { get; }
+
+		/// <summary>
+		/// Gets the link status.
+		/// </summary>
+		ConnectionStatus LinkStatus { get; }
 
 		/// <summary>
 		/// Gets the nominal transmit distance at which the Antenna behaves just as prescribed by Squad's config.
@@ -65,12 +87,6 @@
 		/// The first CelestialBody blocking line of sight to a 
 		/// </summary>
 		CelestialBody firstOccludingBody { get; }
-
-		/// <summary>
-		/// Gets a value indicating whether this <see cref="AntennaRange.IAntennaRelay"/> Relay is communicating
-		/// directly with Kerbin.
-		/// </summary>
-		bool KerbinDirect { get; }
 
 		/// <summary>
 		/// Gets the Part title.

--- a/ModuleLimitedDataTransmitter.cs
+++ b/ModuleLimitedDataTransmitter.cs
@@ -2,7 +2,7 @@
 //
 // ModuleLimitedDataTransmitter.cs
 //
-// Copyright © 2014, toadicus
+// Copyright © 2014-2015, toadicus
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without modification,
@@ -61,13 +61,20 @@
 		private ScreenMessage ErrorMsg;
 
 		/// <summary>
-		/// The distance from Kerbin at which the antenna will perform exactly as prescribed by packetResourceCost
-		/// and packetSize.
+		/// When additive ranges are enabled, the distance from Kerbin at which the antenna will perform exactly as
+		/// prescribed by packetResourceCost and packetSize.
 		/// </summary>
 		[KSPField(isPersistant = false)]
 		public double nominalRange;
 
 		/// <summary>
+		/// When additive ranges are disabled, the distance from Kerbin at which the antenna will perform exactly as
+		/// prescribed by packetResourceCost and packetSize.
+		/// </summary>
+		[KSPField(isPersistant = false)]
+		public double simpleRange;
+
+		/// <summary>
 		/// Relay status string for use in action menus.
 		/// </summary>
 		[KSPField(isPersistant = false, guiActive = true, guiName = "Status")]
@@ -86,9 +93,15 @@
 		public string UItransmitDistance;
 
 		/// <summary>
+		/// The nominal range string for use in action menus.
+		/// </summary>
+		[KSPField(isPersistant = false, guiActive = true, guiName = "Nominal Range")]
+		public string UInominalLinkDistance;
+
+		/// <summary>
 		/// Maximum distance string for use in action menus.
 		/// </summary>
-		[KSPField(isPersistant = false, guiActive = true, guiName = "Maximum Distance")]
+		[KSPField(isPersistant = false, guiActive = true, guiName = "Maximum Range")]
 		public string UImaxTransmitDistance;
 
 		/// <summary>
@@ -145,13 +158,22 @@
 				{
 					return base.vessel;
 				}
-				else if (this.part != null)
+				else if (this.part != null && this.part.vessel != null)
 				{
 					return this.part.vessel;
 				}
-
+				else if (
+					this.part.protoPartSnapshot != null &&
+					this.part.protoPartSnapshot.pVesselRef != null &&
+					this.part.protoPartSnapshot.pVesselRef.vesselRef != null
+				)
+				{
+					return this.part.protoPartSnapshot.pVesselRef.vesselRef;
+				}
 				else
 				{
+					this.LogError("Vessel and/or part reference are null, returning null vessel.");
+					this.LogError(new System.Diagnostics.StackTrace().ToString());
 					return null;
 				}
 			}
@@ -174,9 +196,58 @@
 		}
 
 		/// <summary>
+		/// Gets a value indicating whether this <see cref="AntennaRange.IAntennaRelay"/> Relay is communicating
+		/// directly with Kerbin.
+		/// </summary>
+		public bool KerbinDirect
+		{
+			get
+			{
+				if (this.relay != null)
+				{
+					return this.relay.KerbinDirect;
+				}
+
+				return false;
+			}
+		}
+
+		/// <summary>
+		/// Gets or sets the nominal link distance, in meters.
+		/// </summary>
+		public double NominalLinkSqrDistance
+		{
+			get
+			{
+				if (this.relay != null)
+				{
+					return this.relay.NominalLinkSqrDistance;
+				}
+
+				return 0d;
+			}
+		}
+
+		/// <summary>
+		/// Gets or sets the maximum link distance, in meters.
+		/// </summary>
+		public double MaximumLinkSqrDistance
+		{
+			get
+			{
+				if (this.relay != null)
+				{
+					return this.relay.MaximumLinkSqrDistance;
+				}
+
+				return 0d;
+			}
+		}
+
+		/// <summary>
 		/// Gets the distance to the nearest relay or Kerbin, whichever is closer.
 		/// </summary>
-		public double transmitDistance
+		public double CurrentLinkSqrDistance
 		{
 			get
 			{
@@ -185,7 +256,23 @@
 					return double.PositiveInfinity;
 				}
 
-				return this.relay.transmitDistance;
+				return this.relay.CurrentLinkSqrDistance;
+			}
+		}
+
+		/// <summary>
+		/// Gets the link status.
+		/// </summary>
+		public ConnectionStatus LinkStatus
+		{
+			get
+			{
+				if (this.relay == null)
+				{
+					return ConnectionStatus.None;
+				}
+
+				return this.relay.LinkStatus;
 			}
 		}
 
@@ -196,7 +283,14 @@
 		{
 			get
 			{
-				return this.nominalRange;
+				if (ARConfiguration.UseAdditiveRanges)
+				{
+					return this.nominalRange;
+				}
+				else
+				{
+					return this.simpleRange;
+				}
 			}
 		}
 
@@ -205,11 +299,8 @@
 		/// </summary>
 		public double maxTransmitDistance
 		{
-			get
-			{
-				// TODO: Cache this in a way that doesn't break everything.
-				return Math.Sqrt(this.maxPowerFactor) * this.nominalRange;
-			}
+			get;
+			protected set;
 		}
 
 		/// <summary>
@@ -292,23 +383,6 @@
 		}
 
 		/// <summary>
-		/// Gets a value indicating whether this <see cref="AntennaRange.IAntennaRelay"/> Relay is communicating
-		/// directly with Kerbin.
-		/// </summary>
-		public bool KerbinDirect
-		{
-			get
-			{
-				if (this.relay != null)
-				{
-					return this.relay.KerbinDirect;
-				}
-
-				return false;
-			}
-		}
-
-		/// <summary>
 		/// Gets the Part title.
 		/// </summary>
 		public string Title
@@ -348,13 +422,13 @@
 				"{0} loaded:\n" +
 				"packetSize: {1}\n" +
 				"packetResourceCost: {2}\n" +
-				"nominalRange: {3}\n" +
+				"nominalTransmitDistance: {3}\n" +
 				"maxPowerFactor: {4}\n" +
 				"maxDataFactor: {5}\n",
 				this.name,
 				base.packetSize,
 				this._basepacketResourceCost,
-				this.nominalRange,
+				this.nominalTransmitDistance,
 				this.maxPowerFactor,
 				this.maxDataFactor
 			));
@@ -370,11 +444,13 @@
 
 			if (state >= StartState.PreLaunch)
 			{
+				this.maxTransmitDistance = Math.Sqrt(this.maxPowerFactor) * this.nominalTransmitDistance;
+
 				this.relay = new AntennaRelay(this);
+				this.relay.nominalTransmitDistance = this.nominalTransmitDistance;
 				this.relay.maxTransmitDistance = this.maxTransmitDistance;
-				this.relay.nominalTransmitDistance = this.nominalRange;
-
-				this.UImaxTransmitDistance = Tools.MuMech_ToSI(this.maxTransmitDistance) + "m";
+
+				this.UImaxTransmitDistance = string.Format(Tools.SIFormatter, "{0:S3}m", this.maxTransmitDistance);
 
 				GameEvents.onPartActionUICreate.Add(this.onPartActionUICreate);
 				GameEvents.onPartActionUIDismiss.Add(this.onPartActionUIDismiss);
@@ -393,6 +469,8 @@
 			base.Fields.Load(node);
 
 			base.OnLoad (node);
+
+			this.maxTransmitDistance = Math.Sqrt(this.maxPowerFactor) * this.nominalTransmitDistance;
 		}
 
 		/// <summary>
@@ -400,9 +478,17 @@
 		/// </summary>
 		public override string GetInfo()
 		{
-			string text = base.GetInfo();
-			text += "Nominal Range: " + Tools.MuMech_ToSI((double)this.nominalRange, 2) + "m\n";
-			text += "Maximum Range: " + Tools.MuMech_ToSI((double)this.maxTransmitDistance, 2) + "m\n";
+			StringBuilder sb = Tools.GetStringBuilder();
+			string text;
+
+			sb.Append(base.GetInfo());
+			sb.AppendFormat(Tools.SIFormatter, "Nominal Range: {0:S3}m\n", this.nominalTransmitDistance);
+			sb.AppendFormat(Tools.SIFormatter, "Maximum Range: {0:S3}m\n", this.maxTransmitDistance);
+
+			text = sb.ToString();
+
+			Tools.PutStringBuilder(sb);
+
 			return text;
 		}
 
@@ -569,7 +655,7 @@
 			}
 
 			Tools.PostDebugMessage (
-				"distance: " + this.transmitDistance
+				"distance: " + this.CurrentLinkSqrDistance
 				+ " packetSize: " + this.packetSize
 				+ " packetResourceCost: " + this.packetResourceCost
 			);
@@ -602,7 +688,7 @@
 			PreTransmit_SetPacketResourceCost ();
 
 			Tools.PostDebugMessage (
-				"distance: " + this.transmitDistance
+				"distance: " + this.CurrentLinkSqrDistance
 				+ " packetSize: " + this.packetSize
 				+ " packetResourceCost: " + this.packetResourceCost
 				);
@@ -626,24 +712,32 @@
 		{
 			if (this.actionUIUpdate)
 			{
+				this.UImaxTransmitDistance = string.Format(Tools.SIFormatter, "{0:S3}m",
+					Math.Sqrt(this.MaximumLinkSqrDistance));
+				this.UInominalLinkDistance = string.Format(Tools.SIFormatter, "{0:S3}m",
+					Math.Sqrt(this.NominalLinkSqrDistance));
+				
 				if (this.CanTransmit())
 				{
-					this.UIrelayStatus = "Connected";
-					this.UItransmitDistance = Tools.MuMech_ToSI(this.transmitDistance) + "m";
-					this.UIpacketSize = Tools.MuMech_ToSI(this.DataRate) + "MiT";
-					this.UIpacketCost = Tools.MuMech_ToSI(this.DataResourceCost) + "E";
+					this.UIrelayStatus = this.LinkStatus.ToString();
+					this.UItransmitDistance = string.Format(Tools.SIFormatter, "{0:S3}m",
+						Math.Sqrt(this.CurrentLinkSqrDistance));
+					this.UIpacketSize = string.Format(Tools.SIFormatter, "{0:S3}MiT", this.DataRate);
+					this.UIpacketCost = string.Format(Tools.SIFormatter, "{0:S3}EC", this.DataResourceCost);
 				}
 				else
 				{
 					if (this.relay.firstOccludingBody == null)
 					{
+						this.UItransmitDistance = string.Format(Tools.SIFormatter, "{0:S3}m",
+							Math.Sqrt(this.CurrentLinkSqrDistance));
 						this.UIrelayStatus = "Out of range";
 					}
 					else
 					{
+						this.UItransmitDistance = "N/A";
 						this.UIrelayStatus = string.Format("Blocked by {0}", this.relay.firstOccludingBody.bodyName);
 					}
-					this.UImaxTransmitDistance = "N/A";
 					this.UIpacketSize = "N/A";
 					this.UIpacketCost = "N/A";
 				}
@@ -736,17 +830,15 @@
 		// transmission fails (see CanTransmit).
 		private void PreTransmit_SetPacketResourceCost()
 		{
-			if (ARConfiguration.FixedPowerCost || this.transmitDistance <= this.nominalRange)
+			if (ARConfiguration.FixedPowerCost || this.CurrentLinkSqrDistance <= this.NominalLinkSqrDistance)
 			{
 				base.packetResourceCost = this._basepacketResourceCost;
 			}
 			else
 			{
-				float rangeFactor = (float)(this.transmitDistance / this.nominalRange);
-				rangeFactor *= rangeFactor;
-
-				base.packetResourceCost = this._basepacketResourceCost
-					* rangeFactor;
+				float rangeFactor = (float)(this.CurrentLinkSqrDistance / this.NominalLinkSqrDistance);
+
+				base.packetResourceCost = this._basepacketResourceCost * rangeFactor;
 			}
 
 			base.packetResourceCost *= this.packetThrottle / 100f;
@@ -756,18 +848,18 @@
 		// distance.  packetSize maxes out at _basepacketSize * maxDataFactor.
 		private void PreTransmit_SetPacketSize()
 		{
-			if (!ARConfiguration.FixedPowerCost && this.transmitDistance >= this.nominalRange)
+			if (!ARConfiguration.FixedPowerCost && this.CurrentLinkSqrDistance >= this.NominalLinkSqrDistance)
 			{
 				base.packetSize = this._basepacketSize;
 			}
 			else
 			{
-				float rangeFactor = (float)(this.nominalRange / this.transmitDistance);
-				rangeFactor *= rangeFactor;
+				float rangeFactor = (float)(this.NominalLinkSqrDistance / this.CurrentLinkSqrDistance);
 
 				base.packetSize = Mathf.Min(
 					this._basepacketSize * rangeFactor,
-					this._basepacketSize * this.maxDataFactor);
+					this._basepacketSize * this.maxDataFactor
+				);
 			}
 
 			base.packetSize *= this.packetThrottle / 100f;

--- a/Properties/AssemblyInfo.cs
+++ b/Properties/AssemblyInfo.cs
@@ -2,7 +2,7 @@
 //
 // AssemblyInfo.cs
 //
-// Copyright © 2014, toadicus
+// Copyright © 2014-2015, toadicus
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without modification,
@@ -39,7 +39,7 @@
 // The assembly version has the format "{Major}.{Minor}.{Build}.{Revision}".
 // The form "{Major}.{Minor}.*" will automatically update the build and revision,
 // and "{Major}.{Minor}.{Build}.*" will update just the revision.
-[assembly: AssemblyVersion("1.8.*")]
+[assembly: AssemblyVersion("1.9.*")]
 // The following attributes are used to specify the signing key for the assembly,
 // if desired. See the Mono documentation for more information about signing.
 //[assembly: AssemblyDelaySign(false)]

--- a/ProtoAntennaRelay.cs
+++ b/ProtoAntennaRelay.cs
@@ -2,7 +2,7 @@
 //
 // ProtoAntennaRelay.cs
 //
-// Copyright © 2014, toadicus
+// Copyright © 2014-2015, toadicus
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without modification,
@@ -48,17 +48,24 @@
 		{
 			get
 			{
-				if (this.protoPart != null && this.protoPart.pVesselRef != null)
+				if (
+					this.protoPart != null &&
+					this.protoPart.pVesselRef != null &&
+					this.protoPart.pVesselRef.vesselRef != null
+				)
 				{
 					return this.protoPart.pVesselRef.vesselRef;
 				}
 				else
 				{
-					Tools.PostLogMessage("{0}: Could not fetch vessel!  {1}{2}{3}",
+					Tools.PostErrorMessage("{0}: Could not fetch vessel!  {1}{2}{3}",
 						this.ToString(),
-						this.protoPart == null ? "\n\tprotoPart=Null" : string.Empty,
-						this.protoPart != null && this.protoPart.pVesselRef == null ? "\n\tthis.protoPart.pVesselRef=Null" : string.Empty,
-						this.protoPart != null && this.protoPart.pVesselRef != null && this.protoPart.pVesselRef.vesselRef == null ? "\n\tthis.protoPart.pVesselRef.vesselRef=Null" : string.Empty
+						this.protoPart == null ? "\n\tprotoPart=null" : string.Empty,
+						this.protoPart != null && this.protoPart.pVesselRef == null ?
+							"\n\tthis.protoPart.pVesselRef=null" : string.Empty,
+						this.protoPart != null && this.protoPart.pVesselRef != null &&
+							this.protoPart.pVesselRef.vesselRef == null ?
+							"\n\tthis.protoPart.pVesselRef.vesselRef=null" : string.Empty
 					);
 					return null;
 				}

--- a/RelayDatabase.cs
+++ b/RelayDatabase.cs
@@ -2,7 +2,7 @@
 //
 // RelayDatabase.cs
 //
-// Copyright © 2014, toadicus
+// Copyright © 2014-2015, toadicus
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without modification,
@@ -37,27 +37,8 @@
 
 namespace AntennaRange
 {
-	public class RelayDatabase
+	public class RelayDatabase : Singleton<RelayDatabase>
 	{
-		/*
-		 * Static members
-		 * */
-		// Singleton storage
-		private static RelayDatabase _instance;
-		// Gets the singleton
-		public static RelayDatabase Instance
-		{
-			get
-			{	
-				if (_instance == null)
-				{
-					_instance = new RelayDatabase();
-				}
-
-				return _instance;
-			}
-		}
-
 		/*
 		 * Instance members
 		 * */
@@ -72,9 +53,6 @@
 		// Vessel.id-keyed hash table of part counts, used for caching
 		private Dictionary<Guid, int> vesselPartCountTable;
 
-		// Vessel.id-keyed hash table of booleans to track what vessels have been checked so far this time.
-		public Dictionary<Guid, bool> CheckedVesselsTable;
-
 		private int cacheHits;
 		private int cacheMisses;
 
@@ -117,9 +95,25 @@
 		// Remove a vessel from the cache, if it exists.
 		public void DirtyVessel(Vessel vessel)
 		{
+			#if DEBUG
+			Tools.PostDebugMessage("RelayDatabase: Dirtying cache for vessel {0} in frame {1}",
+				vessel, new System.Diagnostics.StackTrace().ToString());
+			#else
+			Tools.PostLogMessage("RelayDatabase: Dirtying cache for vessel {0}", vessel.vesselName);
+			#endif
+
 			this.relayDatabase.Remove(vessel.id);
 			this.vesselPartCountTable.Remove(vessel.id);
-			this.relayDatabase.Remove(vessel.id);
+			this.bestRelayTable.Remove(vessel.id);
+		}
+
+		public void ClearCache()
+		{
+			Tools.PostLogMessage("RelayDatabase: onSceneChange clearing entire cache.");
+
+			this.relayDatabase.Clear();
+			this.bestRelayTable.Clear();
+			this.vesselPartCountTable.Clear();
 		}
 
 		// Returns true if both the relayDatabase and the vesselPartCountDB contain the vessel id.
@@ -228,12 +222,35 @@
 		// Runs when the player requests a scene change, such as when changing vessels or leaving flight.
 		private void onSceneChange(GameScenes scene)
 		{
-			// If the active vessel is a real thing...
-			if (FlightGlobals.ActiveVessel != null)
-			{
-				// ... dirty its cache
-				this.onVesselEvent(FlightGlobals.ActiveVessel);
-			}
+			Tools.PostDebugMessage(
+				"RelayDatabase: caught onSceneChangeRequested in scene {0} to scene {1}.  ActiveVessel is {2}",
+				HighLogic.LoadedScene,
+				scene,
+				FlightGlobals.ActiveVessel == null ? "null" : FlightGlobals.ActiveVessel.vesselName
+			);
+
+			if (scene == GameScenes.FLIGHT)
+			{
+				if (scene == HighLogic.LoadedScene)
+				{
+					if (FlightGlobals.ActiveVessel != null)
+					{
+						Tools.PostDebugMessage("RelayDatabase: onSceneChange clearing {0} from cache.",
+							FlightGlobals.ActiveVessel.vesselName);
+
+						this.onVesselEvent(FlightGlobals.ActiveVessel);
+					}
+				}
+				else
+				{
+					this.ClearCache();
+				}
+			}
+		}
+
+		private void onGameLoaded(object data)
+		{
+			this.ClearCache();
 		}
 
 		// Runs when parts are undocked
@@ -394,7 +411,6 @@
 			this.relayDatabase = new Dictionary<Guid, List<IAntennaRelay>>();
 			this.bestRelayTable = new Dictionary<Guid, IAntennaRelay>();
 			this.vesselPartCountTable = new Dictionary<Guid, int>();
-			this.CheckedVesselsTable = new Dictionary<Guid, bool>();
 
 			this.cacheHits = 0;
 			this.cacheMisses = 0;
@@ -406,6 +422,7 @@
 			GameEvents.onGameSceneLoadRequested.Add(this.onSceneChange);
 			GameEvents.onPartCouple.Add(this.onFromPartToPartEvent);
 			GameEvents.onPartUndock.Add(this.onPartEvent);
+			GameEvents.onGameStateLoad.Add(this.onGameLoaded);
 		}
 
 		~RelayDatabase()
@@ -417,6 +434,7 @@
 			GameEvents.onGameSceneLoadRequested.Remove(this.onSceneChange);
 			GameEvents.onPartCouple.Remove(this.onFromPartToPartEvent);
 			GameEvents.onPartUndock.Remove(this.onPartEvent);
+			GameEvents.onGameStateLoad.Remove(this.onGameLoaded);
 
 			Tools.PostDebugMessage(this.GetType().Name + " destroyed.");
 

--- a/RelayExtensions.cs
+++ b/RelayExtensions.cs
@@ -2,7 +2,7 @@
 //
 // Extensions.cs
 //
-// Copyright © 2014, toadicus
+// Copyright © 2014-2015, toadicus
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without modification,
@@ -38,6 +38,50 @@
 	public static class RelayExtensions
 	{
 		/// <summary>
+		/// Returns the distance between two IAntennaRelays.
+		/// </summary>
+		/// <param name="relayOne">Relay one.</param>
+		/// <param name="relayTwo">Relay two.</param>
+		public static double DistanceTo(this IAntennaRelay relayOne, IAntennaRelay relayTwo)
+		{
+			return relayOne.vessel.DistanceTo(relayTwo.vessel);
+		}
+
+		/// <summary>
+		/// Returns the distance from this IAntennaRelay to the given CelestialBody
+		/// </summary>
+		/// <param name="relay">Relay.</param>
+		/// <param name="body">Body.</param>
+		public static double SqrDistanceTo(this IAntennaRelay relay, CelestialBody body)
+		{
+			double range = relay.vessel.DistanceTo(body) - body.Radius;
+
+			return range * range;
+		}
+
+		/// <summary>
+		/// Returns the distance between two IAntennaRelays.
+		/// </summary>
+		/// <param name="relayOne">Relay one.</param>
+		/// <param name="relayTwo">Relay two.</param>
+		public static double SqrDistanceTo(this IAntennaRelay relayOne, IAntennaRelay relayTwo)
+		{
+			return relayOne.vessel.sqrDistanceTo(relayTwo.vessel);
+		}
+
+		/// <summary>
+		/// Returns the distance from this IAntennaRelay to the given CelestialBody
+		/// </summary>
+		/// <param name="relay">Relay.</param>
+		/// <param name="body">Body.</param>
+		public static double DistanceTo(this IAntennaRelay relay, CelestialBody body)
+		{
+			double range = relay.vessel.DistanceTo(body) - body.Radius;
+
+			return range;
+		}
+
+		/// <summary>
 		/// Returns the distance between this IAntennaRelay and a Vessel
 		/// </summary>
 		/// <param name="relay">This <see cref="IAntennaRelay"/></param>
@@ -72,7 +116,7 @@
 		/// </summary>
 		/// <param name="relay">This <see cref="IAntennaRelay"/></param>
 		/// <param name="vessel">A <see cref="Vessel"/></param>
-		public static double sqrDistanceTo(this AntennaRelay relay, Vessel vessel)
+		public static double SqrDistanceTo(this AntennaRelay relay, Vessel vessel)
 		{
 			return relay.vessel.sqrDistanceTo(vessel);
 		}
@@ -82,9 +126,11 @@
 		/// </summary>
 		/// <param name="relay">This <see cref="IAntennaRelay"/></param>
 		/// <param name="body">A <see cref="CelestialBody"/></param>
-		public static double sqrDistanceTo(this AntennaRelay relay, CelestialBody body)
-		{
-			return relay.vessel.sqrDistanceTo(body);
+		public static double SqrDistanceTo(this AntennaRelay relay, CelestialBody body)
+		{
+			double dist = (relay.vessel.GetWorldPos3D() - body.position).magnitude - body.Radius;
+
+			return dist * dist;
 		}
 
 		/// <summary>
@@ -92,7 +138,7 @@
 		/// </summary>
 		/// <param name="relayOne">This <see cref="IAntennaRelay"/></param>
 		/// <param name="relayTwo">Another <see cref="IAntennaRelay"/></param>
-		public static double sqrDistanceTo(this AntennaRelay relayOne, IAntennaRelay relayTwo)
+		public static double SqrDistanceTo(this AntennaRelay relayOne, IAntennaRelay relayTwo)
 		{
 			return relayOne.vessel.sqrDistanceTo(relayTwo.vessel);
 		}
@@ -140,10 +186,11 @@
 			for (int rIdx = 0; rIdx < vesselRelays.Count; rIdx++)
 			{
 				relay = vesselRelays[rIdx];
-				if (relay.CanTransmit())
+				if (relay.LinkStatus > ConnectionStatus.None)
 				{
 					canTransmit = true;
-					if (relay.transmitDistance <= relay.nominalTransmitDistance)
+
+					if (relay.LinkStatus == ConnectionStatus.Optimal)
 					{
 						return ConnectionStatus.Optimal;
 					}