Back in the day of the first series of Hertz rental Shelbys, someone I know was involved in renting a mustang and sedately driving to the race track where the engine was pulled and placed into a race car in place of a damaged engine. The race was run, and after a second place finish, the engine was returned to the rental car and sedately driven back to the rental office. So, all rental mustangs aren't so bad, at least until after they are returned.