diff --git a/BizHawk.Emulation.Common/Base Implementations/MemoryDomain.cs b/BizHawk.Emulation.Common/Base Implementations/MemoryDomain.cs
index a75ad4ffbe..3db494bc03 100644
--- a/BizHawk.Emulation.Common/Base Implementations/MemoryDomain.cs	
+++ b/BizHawk.Emulation.Common/Base Implementations/MemoryDomain.cs	
@@ -35,17 +35,6 @@ namespace BizHawk.Emulation.Common
 			return new MemoryDomainByteArray(name, endian, data, writable, wordSize);
 		}
 
-		/// <summary>
-		/// create a memorydomain that references an unmanaged memory block with 16 bit swaps
-		/// </summary>
-		/// <param name="data">must remain valid as long as the MemoryDomain exists!</param>
-		/// <param name="writable">if false, writes will be ignored</param>
-		[Obsolete]
-		public static unsafe MemoryDomain FromIntPtrSwap16(string name, long size, Endian endian, IntPtr data, bool writable = true)
-		{
-			return new MemoryDomainIntPtrSwap16(name, endian, data, size, writable);
-		}
-
 		public override string ToString()
 		{
 			return Name;
diff --git a/BizHawk.Emulation.Cores/Consoles/Sega/gpgx/GPGX.IMemoryDomains.cs b/BizHawk.Emulation.Cores/Consoles/Sega/gpgx/GPGX.IMemoryDomains.cs
index 7bb4b11188..25a7791484 100644
--- a/BizHawk.Emulation.Cores/Consoles/Sega/gpgx/GPGX.IMemoryDomains.cs
+++ b/BizHawk.Emulation.Cores/Consoles/Sega/gpgx/GPGX.IMemoryDomains.cs
@@ -42,11 +42,10 @@ namespace BizHawk.Emulation.Cores.Consoles.Sega.gpgx
 				}
 
 				else
-				{
-					// TODO: are the Z80 domains really Swap16 in the core?  Check this
-					//var byteSize = name.Contains("Z80") ? 1 : 2;
-					mm.Add(MemoryDomain.FromIntPtrSwap16(name, size,
-						MemoryDomain.Endian.Big, area, name != "MD CART" && name != "CD BOOT ROM"));
+				{
+					// TODO: are the Z80 domains really Swap16 in the core?  Check this
+					//var byteSize = name.Contains("Z80") ? 1 : 2;
+					mm.Add(new MemoryDomainIntPtrSwap16(name, MemoryDomain.Endian.Big, area, size, name != "MD CART" && name != "CD BOOT ROM"));
 				}
 			}
 			var m68Bus = new MemoryDomainDelegate("M68K BUS", 0x1000000, MemoryDomain.Endian.Big,
diff --git a/BizHawk.Emulation.Cores/Consoles/Sega/gpgx64/GPGX.IMemoryDomains.cs b/BizHawk.Emulation.Cores/Consoles/Sega/gpgx64/GPGX.IMemoryDomains.cs
index c6b3ce55ee..dad131593d 100644
--- a/BizHawk.Emulation.Cores/Consoles/Sega/gpgx64/GPGX.IMemoryDomains.cs
+++ b/BizHawk.Emulation.Cores/Consoles/Sega/gpgx64/GPGX.IMemoryDomains.cs
@@ -44,19 +44,19 @@ namespace BizHawk.Emulation.Cores.Consoles.Sega.gpgx64
 				else
 				{
 					// TODO: are the Z80 domains really Swap16 in the core?  Check this
-					mm.Add(MemoryDomain.FromIntPtrSwap16(name, size,
-						MemoryDomain.Endian.Big, area, name != "MD CART" && name != "CD BOOT ROM"));
+					mm.Add(new MemoryDomainIntPtrSwap16(name, MemoryDomain.Endian.Big, area, size, true));
 				}
 			}
+
 			var m68Bus = new MemoryDomainDelegate("M68K BUS", 0x1000000, MemoryDomain.Endian.Big,
-				delegate (long addr)
+				delegate(long addr)
 				{
 					var a = (uint)addr;
 					if (a >= 0x1000000)
 						throw new ArgumentOutOfRangeException();
 					return Core.gpgx_peek_m68k_bus(a);
 				},
-				delegate (long addr, byte val)
+				delegate(long addr, byte val)
 				{
 					var a = (uint)addr;
 					if (a >= 0x1000000)
@@ -67,14 +67,14 @@ namespace BizHawk.Emulation.Cores.Consoles.Sega.gpgx64
 			mm.Add(m68Bus);
 
 			var s68Bus = new MemoryDomainDelegate("S68K BUS", 0x1000000, MemoryDomain.Endian.Big,
-				delegate (long addr)
+				delegate(long addr)
 				{
 					var a = (uint)addr;
 					if (a >= 0x1000000)
 						throw new ArgumentOutOfRangeException();
 					return Core.gpgx_peek_s68k_bus(a);
 				},
-				delegate (long addr, byte val)
+				delegate(long addr, byte val)
 				{
 					var a = (uint)addr;
 					if (a >= 0x1000000)