I have Nelson Hobby Specialties water reducible polyurethane paint (brushed on) on my test stand, which gets slobbered in fuel, and it has stood up well more than a year. This was the recommendation of the stand mfr. I looked at the Minwax offerings, and the only water miscible product of theirs I could find was labelled "not for exterior use" so I shied away from it. Their polyurethane spar varnish, which is ok for external use, was not so cheap, so I spent a little extra for something made for rc use.