What is the best Ps2 to USB controller adapter?

My crappy Logitech Wingman has gone its last round of Street Fighter 2. Every pc controller I have seen is complete garbage. I'm about to break down and get a PS2 to USB adapter so I can use my Street Fighter controller for MAME. My question is, which one is the best investment?

I'd go with the Magic Box or the EMS Dual...both available from Lik-Sang. Almost none of the newer ones have the lag problems that the old ones have.

I've been using the PSX>USB converter from radio shack for a couple years now and its still kicking. I think it was around $10.