I have a Duralast Gold from Autozone, and havent had any probs with it, using 3 amps and turbo, and a UDP. It has a lifetime warrenty with it too. A true, high amp alternator will be very expensive. Usually around 500-600 bucks.

13.5 @108 MPH-2.2 60ft(stupid FWD!)
S16G @ 18 PSI/FMIC/Running on MegaSquirt II (Now with sequential
fuel injection)
My webpage: http://eclipsed4evr.home.comcast.net
-1998 Mitsubishi Eclipse RS-T- "Toy"
-1992 Plymouth Laser Turbo AWD(SOLD)
-2000 Honda CR-V(daily)