The question has come up a few times on using PL Premium as a coating and the main issue seems to be that it is has no UV protection. However, you mentioned that you use it on the keel. I hadn't thought of this earlier but why not use it on the hull since the hull really doesn't see much UV. Then another coating (paint) can be used for deck surfaces.....just a thought.

: I'm not going out in the dark to look at my paint cans to see if
: the word enamel is used, but, basically, Rustoleum has oil based
: paints and water based paints - if you thin it with mineral
: spirits, instead of water, it's OK to use on the polyester.
: Other hardware store brands are the same.

: And, I'll just throw this out there. A first layer of thinly spread
: PL PRemium Construction Adhesive, by Loctite, at least along the
: keel line, followed by the paint after it dries, definitely gets
: my vote. That will not flake or scrape off, pretty much no
: matter what you do. It doesn't have any uv protection, hence the
: need for paint over it.
: Try it on a piece of scrap fabric and see.
: Just paint works fine, though!