I occasionally sold them. They have a limited range of vehicles that it fits on, and I wouldn't trust it with a heavy bike. Thule & Yakima racks tend to be sturdier. All boot mounted racks which have parts sitting on paintwork will damage it eventually. Making sure that the paintwork and rack are clean, and removing it wherever not in use will help. If Saris claim it fits your vehicle, it shouldn't shift around if correctly fitted. If it is used on something they don't explicitly claim is compatible, all bets are off.