Had a powder coated bumper and rock rails on my old xj. I hated it, any scratches can't be repaired, well you can- but it doesn't look right and won't last. Bubbled and flaked too. Could have been a lousy job? Basically for anything that might come into contact with another surface I would stay away from powder coating. Personally a king can of flat black tremclad (professional series of course) and go to town. Cheap and easy to touch up after you kiss those rocks.