VirtualListView - add a UseCustomBackground flag true by default, if set to false it will bypass custom background drawing logic resulting in that speedboost I keep doing checkins for. Refactor RamWatch to check if there is any need to draw ahead of time and set this flag. Most of the time this will result is a good speed boost for this dialog, only if they are watching a frozen address (which isn't very exciting anyway) or an out of range address (which they need to fix) do they suffer the speed cost of background drawing

BizHawk.Client.Common/tools/Watch.cs

@@ -202,6 +202,14 @@ namespace BizHawk.Client.Common
 
 		public void ClearChangeCount() { _changecount = 0; }
 
+		public bool IsOutOfRange
+		{
+			get
+			{
+				return !IsSeparator && Address.Value >= Domain.Size;
+			}
+		}
+
 		public string Notes { get { return _notes; } set { _notes = value; } }
 
 		public static Watch GenerateWatch(MemoryDomain domain, int address, WatchSize size, DisplayType type, string notes, bool bigEndian)

BizHawk.Client.EmuHawk/CustomControls/VirtualListView.cs

@@ -434,6 +434,8 @@ namespace BizHawk.Client.EmuHawk
 			View = View.Details;
 			Sorting = SortOrder.None;
 
+			UseCustomBackground = true;
+
 			ptrlvhti = Marshal.AllocHGlobal(Marshal.SizeOf(typeof(LvHitTestInfo)));
 
 			SetStyle(ControlStyles.OptimizedDoubleBuffer, true);
@@ -625,7 +627,7 @@ namespace BizHawk.Client.EmuHawk
 							OnCustomDrawNotice(ref m);
 							messageProcessed = true;
 
-							if (QueryItemBkColor == null)
+							if (QueryItemBkColor == null || !UseCustomBackground)
 							{
 								m.Result = (IntPtr)0;
 							}
@@ -674,6 +676,7 @@ namespace BizHawk.Client.EmuHawk
 		}
 
 		public bool BlazingFast { get; set; }
+		public bool UseCustomBackground { get; set; }
 
 		protected ListViewItem GetItem(int idx) 
 		{

BizHawk.Client.EmuHawk/tools/Watch/RamWatch.cs

@@ -237,11 +237,33 @@ namespace BizHawk.Client.EmuHawk
 				}
 
 				WatchListView.BlazingFast = true;
+				WatchListView.UseCustomBackground = NeedsBackground;
 				WatchListView.ItemCount = _watches.Count;
 				WatchListView.BlazingFast = false;
 			}
 		}
 
+		private bool NeedsBackground
+		{
+			get
+			{
+				foreach(var watch in _watches)
+				{
+					if (Global.CheatList.IsActive(_watches.Domain, watch.Address ?? 0))
+					{
+						return true;
+					}
+
+					if (watch.IsOutOfRange)
+					{
+						return true;
+					}
+				}
+
+				return false;
+			}
+		}
+
 		public void FastUpdate()
 		{
 			if (_paused)