basically you will lose big in the milage and reliablity department. I hear that superchargers require less maintenence then turbos. A turbo will give you great high end power, and a supercharger will give you better low end torque. if you go with either you will probably either have to get lower compression pistons or run a really low boost. a higher volume/flow oil pump is a good idea and some sort of copper/solid metal headgasket will help. either option is very expensive, so make your decision wisely.