There’s a reason my friend.
Kawaks has serious desync issues with almost all Neo Geo games. There are exceptions like Garou: MOTW, but stuff like KOF 98, SS4, Last Blade 2, etc, all desync within like 5 minutes.
Also, you can make things look just about as good in MAME with the right settings, just takes a little more tinkering.
Mame also has more options than kawaks does.
Especially regarding online play.
The only thing Kawaks has going for it really is less input lag.
As for the first poster, don’t use full screen mode.
If you want good Mame settings, do this:
1024x768 windowed (non-fullscreen, whatever)
Horizontal Scanlines 75%
Enable FM synthesis in sound options, and make sure it’s set to at least 44, 000 KHZ.