Jetta Superchargers

Ok im the kind of guy that goes for Insta-Power when the gas comes in. SO im interested in buying a supercharger. Which ones are recommended for the 2.0 8v. ? I would love to get more out of it than a measly 7 psi. I have heard that you can make them spin up 15 psi with high performance pulleys. Please help me in finding all of this stuff,

tanx ^.^

i was told that neuspeed was made the best but if you have a stick go turbo if not (automatic) go with the neuspeed supercharger thats what im doing