They'd be able to withstand minor bumps and scrapes. But most likely would not withstand a full blow, or if the lip got ripped off the car. I've had my WW RS lip rip off my front bumper and got run over on the fast lane on the freeway. I went back for it to pick it up and the only thing that was damaged was the paint. That's the great thing about urethane. I doubt that an ABS plastic lip could withstand the exact same punishment...