PlayStation DualShock 2 + USB Adapter, using the exact same configuration at the PS2 version of GTA.
good things:
left analog up/down = lean foward/backward in bike, and camera top/bottom in car. ( no need to "tap" buttons to go faster 
)
Right analog = Camera, I can look ahead of turns , and up /down hills when racing 
can do "slight" turns, no need to tap there again for little turns.
Can press way more keys at the same time
I tried once to fly with keyboard... eeek pain
I'm thinking of recording myself playing once, screen + hands on controller, just for the sake of it
Exactly the same as Knuckles...been using a trusty Sony PS2 pad on a PC for years now. I hate Sony, but I love their pads, best you can get! With MTA, it was just natural to use a pad after so many years of playing GTA3, VC and SA on a PS2 so to have the same config for MTA is wicked.
I would have thought using a pad would be a big advantage for the reasons Knuckles says, but I still get regularly out drove by the likes of Mr Dogshit and Micro who use use the keyboard, so it seems like there is no substitute for good old fasioned skill in MTA...
