I've come to the conclusion from some of my friends in the MacMAME community that upgrading my G3 for my arcade cabinet is a good idea. This will allow me to get a boost in speed for minimal price. The first upgrade would be to bump my 350mhz G3 to an Encore/ZIF G3 500Mhz CPU. The second is to install an ATI Radeon 7000 video card.

The CPU upgrade obviously speeds things up and surprisingly so does the video card (since MacMAME takes advantage of OpenGL). Another added benefit to the video card is that it has TV out, something I'll need eventually anyway. Total upgrade price: $300. Not bad. After this I should be able to play almost all of the Neo-Geo and CPS2 games at close to full speed.