It's without a doubt TAC-2 for me. The one with the metal stick, the plastic one doesn't make the same familiar sound. :-D
When I first played the C64 the joystick of choice for everyone I knew was "The Boss". It did suck majorly though, but I guess we'd never used anything else back then. ;-)
I did have a Quickshot (I think it was called that) that was lovely, until I broke it in two during a frantic game of Ace on my C64.
And Cheetah's The Bug was great too.
