I never had much chance to play Street Fighter Alpha over the years, but I recently got my hands on the SNES version of the 2nd game.
Alpha 2 of course started in the arcades, and that version looks much better than the SNES one.
The graphics and sound do take a bit of a hit, but I didn't find it to be too troubling. There is a delay at the start of the match, that is a little annoying at first. Granted it doesn't effect your match at all. Another difference is (I believe) that some characters like Cammy White aren't available in the Super Nintendo version.
The gameplay holds up pretty well, even after all these years. I like the fast speed, the power bar, and balanced difficulty. Granted the SNES version is never going to be the best version to have, I've quite enjoyed playing through it. I really need to get my hands on more Alpha games.
Score: 8 out of 10