Wow, thanks for all the responses.
Kanedo, sorry, the link I meant to paste were to those Competition buttons, not the standard ones. But yeah, those are them.
The arcade I goto has those Perfect 360's. I'm a little sloppy on some things with them just because I'm too accustomed to traditional clicking sticks, but they're definately more responsive. They're paired with those competition buttons and it's definately a 'quick' setup for lack of a better term.
As far as the guts of the machine go, right now it looks like a PS2 with room in the cabinet for a PC alongside in the future. I already own most of the games for the Playstation anyhow. The emulators today are already amazing and can do up to Alpha3, however lately I've been playing alot of CvS2 and unfortunately that's only on a console for now.
A modded DC with a VGA adapter on a 25" RGB Arcade monitor at 640 would be slick. Too bad about the DC's support for future games.
So yeah, that's it in a nutshell so far. An engineering friend at work is helping me design the cab in ProEngineer, which is great for visualization and creating blueprints. It's all still very early though.