I have personally never hitten one, but when i was in the car with my brothers GF, she was really flying down the road in her car and as she came round a corner, she hit the bump at about 55mph. Because the car is so low (Ford Racing Puma), she instantly ripped the front bumper off which then went under the wheels. She also buckled both front wheels. She did get a little air but surprisingly, there was no suspension damage. Still, it was expensive to fix, and scary as hell!