diff --git a/src/BizHawk.Emulation.Cores/Consoles/Magnavox/Odyssey2/O2Hawk.cs b/src/BizHawk.Emulation.Cores/Consoles/Magnavox/Odyssey2/O2Hawk.cs
index 462d710a28..fa0d8850d6 100644
--- a/src/BizHawk.Emulation.Cores/Consoles/Magnavox/Odyssey2/O2Hawk.cs
+++ b/src/BizHawk.Emulation.Cores/Consoles/Magnavox/Odyssey2/O2Hawk.cs
@@ -85,7 +85,7 @@ namespace BizHawk.Emulation.Cores.Consoles.O2Hawk
 			cpu.SetCallbacks(ReadMemory, PeekMemory, PeekMemory, WriteMemory);
 
 			// set up differences between PAL and NTSC systems
-			if ((game.Region == "US" || game.Region == "EU-US" || game.Region == null) && !is_G7400)
+			if (!is_G7400 && game.Region is null or "US" or "EU-US")
 			{
 				is_pal = false;
 				pic_height = 240;
diff --git a/src/BizHawk.Emulation.Cores/Consoles/Nintendo/N64/N64.cs b/src/BizHawk.Emulation.Cores/Consoles/Nintendo/N64/N64.cs
index ae7411aa2d..212314f118 100644
--- a/src/BizHawk.Emulation.Cores/Consoles/Nintendo/N64/N64.cs
+++ b/src/BizHawk.Emulation.Cores/Consoles/Nintendo/N64/N64.cs
@@ -45,7 +45,7 @@ namespace BizHawk.Emulation.Cores.Nintendo.N64
 			_disableExpansionSlot = _syncSettings.DisableExpansionSlot;
 
 			// Override the user's expansion slot setting if it is mentioned in the gamedb (it is mentioned but the game MUST have this setting or else not work
-			if (game.OptionValue("expansionpak") != null && game.OptionValue("expansionpak") == "1")
+			if (game.OptionValue("expansionpak") is "1")
 			{
 				_disableExpansionSlot = false;
 				IsOverridingUserExpansionSlotSetting = true;
diff --git a/src/BizHawk.Emulation.Cores/Consoles/Sega/SMS/SMS.cs b/src/BizHawk.Emulation.Cores/Consoles/Sega/SMS/SMS.cs
index 2a1bc3e152..8b09cbb190 100644
--- a/src/BizHawk.Emulation.Cores/Consoles/Sega/SMS/SMS.cs
+++ b/src/BizHawk.Emulation.Cores/Consoles/Sega/SMS/SMS.cs
@@ -297,7 +297,7 @@ namespace BizHawk.Emulation.Cores.Sega.MasterSystem
 		{
 			if (display == SmsSyncSettings.DisplayTypes.Ntsc) return DisplayType.NTSC;
 			if (display == SmsSyncSettings.DisplayTypes.Pal) return DisplayType.PAL;
-			if (region != null && region == "Europe") return DisplayType.PAL;
+			if (region is "Europe") return DisplayType.PAL;
 			return DisplayType.NTSC;
 		}