I'll have to get back to you in a few years on the Dart. Even though I sold the car recently, the new owner lives nearby so I see it regularly. IIRC the one-step clearcoat finish I have and the two-step finishes are both polyurethane. So far, the one-step is holding up well especially considering that reds have a reputation for going flat quickly. I waxed the car 2x/yr and washed as needed. The car has seen a little rain and no snow. The finish is not cracking or peeling at all. There isn't any road rash showing even after about 25k miles.