I'm thinking of getting a PS3 soon. Part of the reason I'm interested is because it can use USB gamepads, so I can use my arcade stick via USB adapter, and USB Saturn pad.

There's one thing I'm not quite clear on, though. I know that there's a PS button, and some X-->PS3 adaptors include a specific PS button functionality. Do you need a PS button to navigate the menu or launch the game? Can I play with two players using no official PS3 pads, or do I need at least one controller that includes one?

Bonus question: the adaptor I've been using on my computer is the 3 in 1 PC Joy Box, the black Saturn/PS/DC-->USB adaptor. It works fine on my computer with no lag; has anyone tried this on the PS3?