GameEx is the only front end with the most responsive technical support, as a result of it not only being community driven (helping troubleshoot, creating add-ons, etc.) but also developer driven. It's also the most flexible and easy to modify (in general) front ends in my opinion (compared to MaLa and Hyperspin). If you're going with PS2/Wii games I would recommend a i7 processor or similar, and a 2Ghz video card. If N64 or less i3 and 1GHz is more than enough. I'm currently a big fan of toys such as LED blinky, LED buttons, analog joystick (just two at most), 4 player setup. That is how I'm building my cab.