The Porsche Cayenne Turbo Electric is the quickest SUV we've ever tested, reaching 60 mph in just 2.1 seconds and completing the quarter-mile in 9.5 seconds.The braking performance is also the best among SUVs, matching the result of a Corvette ZR1 by stopping from 70 mph in just 140 feet.The Cayenne Turbo Electric also posted the best roadholding figure for an SUV in Car and Driver history at 1.05 g on the skidpad.