pully is ok. its not really gonna give you any power though..maybe 3 whp max and thats stretching it. think more 1-2 whp.
if you have a sound system or whatever in your car though then i wouldn't recommend it. it's an underdrive pulley so it's gonna rob your alternator of power, so if you're milking your battery with extra things it's not a good situation (even if you have an optima yellow top battery).
for only $60 though, it's still a good deal for 2 whp and its pretty easy to install yourself.
i would NOT get the unorthodox crank pulley (ultra s). quite a few peoples engines have blown or been damaged with these on their cars.