I don't have any experience with them myself, but from what I've heard the quality isn't very good. For example the mounting brackets are flimsy and other design features. I believe the general consensus is to put out the extra money and get a vortech.
I've got one and I love it. Never had any issues with it whatsoever. However... This is the only supercharger that I have experience with so..... I can't make any comparisions.
well which ones are you guys talking about. there was an article in a mustang mag (dont remember which mag it was) where they installed a gear driven powerdyne on a 94/95 mustang with decent results.