weight:
front standard 28 pounds each - 20 lbs for optional
rear standard 34 pounds each - 25 lbs for optional
Assuming these weights are accurate; I had heard that the formula is for every 1 lb reduction in a wheel and tire combination (rotating part) equates to roughly a 7 lbs reduction in the weight of the car while in motion. If this rule is accurate a GT with standard wheels has a weight penalty of 239 lbs or a large extra passenger always along for the ride over the GT with optional wheels.
FWIW I too like the std wheel ......Dealer w/b ordering my car w/ std wheel and w/o Mac sound and possibly w/ std black calipers....still trying to decide on color (reason order not placed yet) tween white or tungsten ( either w/ stripes).......Any opinions re colors and ordering w/o the Mac....Thanks Steve