11. Abt R8 GTR

Notable Features: 620 hp, 0-60 mph time of 3.2 seconds, top speed of 201 mph, ceramic brakes, adjustable suspension dampers, weighs 220 lbs less than the Audi R8

Complex Says: All that carbon fiber isn't just for show. The Abt R8 GTR is the epitome of what the Audi R8 can be, when taken to its logical end. It's truly a pity that it isn't available here.