Look at the mileage of the car-has it been properly maintained? SCs are very reliable cars when they receive proper maintenance-oil changes every 3k, tranny flush and fill every 30k, coolant flush and fill mid-fall and mid-spring, plugs every year, wires every third year-differential oil changed every 60k.
Most SCs are driven hard and put up wet-most new owners, unless they have done proper research like you are, don't even know that the supercharger does not get its oil from the engine, it has a self-contained oil supply.
You can do more research at
www.sccoa.com