POR does not chip off if you follow the instructions, you can smack it with a hammer. It's also flexible so if the part expands or bends it will do so along with it.
The only cases I've had POR fall off is if the area wasn't cleaned and prepped properly. It seats on bare 'treated' or 'rusted' metal only. If you're adding multiple thin coats there is a time limitation for re coating ( I think it needs to be re-coated while it's still tacky). I've been using it as a metal primer, and it's awesome. I then top coat with seam sealer and/or paintable rocker guard.
Performance one step at a time.
Last edited by InfiniteDice; 10-26-2011 at 01:36 PM.