Dirt pickup
Poli Glow worked great on the hull of my old C22, where it kept its shine all season. I also used it at first in my cockpit - not on the non-skid deck, but on the vertical fiberglass surfaces. It seemed to pick up a lot of dirt on the side of the cockpit seats, where we would place our feet during heeling. This dirt would not come off with soap, and I had to use the Poli Glow pre-treatment cleaner. You might have the same problem on non-skid, where you get foot traffic.