www.ststurbo.com
However, they don't make a turbo kit for our cars AND the turbo kits they sell seem flawed to me. First thing is the oiling system, they run pressurized oil from your engine, just like a turbo mounted near the engine, however... you've got 6 feet of the life-blood of your engine being exposed to rocks, the elements, etc. Second, the intake tubing is freaking long! It's gotta go from the turbo all the way to the front, up and into the intake...
We need to get some things straight. A properly sized turbo/intercooler will have no lag and just feel more powerful. Your engine just doesn't hit 3000rpm and WHAM, 400 horsepower. It's progressive. The down fall to turbochargers is the heat, you need to worry about plumbing exhaust piping around the engine bay to the other turbo in a twin turbo setup, and then intake piping, etc. The good side is, that it's 'free' horsepower, you use a byproduct of the combustion process to feed it.
Superchargers are good in the respect that they aren't heat driven and provide steady power from idle, just like a larger displacement. The only downfall I can think of would be the belt. At higher boost/rpm levels, they can slip and many-a-races have been lost from a thrown belt....