Fire up the 2012 Ford Shelby GT500 and you are treated to one of the meanest-sounding engines ever built. At idle, the slow rumble murmurs the potential for tire-smoking mayhem. Lay into the throttle and the rumbling becomes a boiling torrent, launching the GT500 forward accompanied by the supercharger's whine that can best be described as addictive.
The GT500 is quite upset in the corners by careless inputs. Maximizing thrills in the curves requires a high level of restraint and a healthy dose of courage. There is plenty of grip, but the Shelby's 3,800 pounds seem poised to break loose at all times. The ride is stiff, but not too harsh in the base model.
Adding the SVT Performance package introduces plenty of harshness, though, and without the expected performance gains. On a polished-smooth racetrack, the SVT option might make sense. But in the real world (of course in the real tracks too) it makes the car skittish. The upgraded tires also tend to snap loose from adhesion, and drift rather gracefully. For all but you should skipping the SVT upgrade.