I reserved a "guaranteed" Mustang GT Premium in June at PHL. Upon arrival, I was told that car was not "carried" anymore but I could have a Camaro. I asked if it was an SS from the Adrenaline Collection and was told yes. In fact, I was assigned a loaded V6 Camaro RS, brand new, 400 miles. Nice ride, but not an SS or Mustang GT. Their answer was "that's what we substitute for the Mustang." As ever, renter beware and, like Big Brother, expect the unexpected.