Unfortunately people dump supercharged skis when they know that the supercharger has taken a crap. Make sure maintenance records are immaculate with timely oil changes and proper supercharger maintenance inspections and rebuilds. Miki is correct on the test ride but make sure you know what to look for when you ride it. Top speed at wot is important. A dealer can do a buyer inspection which must include a supercharger clutch friction test and a also a leak down test on your motor and intercooler.