superchargers are ok. but you have to take power in order to make power. in other words you have to add another pulley which will rob power from your engine, but you come out with more power than you started with. i have heard that sc's take less tuning and are a lot more reliable. personally i like the feel of turbo lag. you get thrown back in the seat and the faster you go the farther back in the seat you go. turbos have more potential in the long run just because of the enormous amounts of boost that you can have, and all of the upgraded parts and what not.
Vortech chargers are more of dyno queens... they put up decent numbers at peak, but that peak is only reached for a split second, everything else in the powerband doesnt even come close to the peak power, just like dc2GS-R said.
anyway my two cents would be...
- turbo > supercharger for high horse power
-supercharger > turbo for reliability and less headache