Has anyone tried using Rustoleum's spar urethane product, (Varathane), on exterior wood? It is a water based urethane. Personally, I have had better results with urethane than with varnish. My toe rails seem to last about half a season even with several build coats with Epifanes varnish. I have used Minwax spar polyurethane on coaming boards and other places, it seems to do pretty well. I have a spot on my toe rails that water seems to be in almost constant contact with, and it always peels away by spring. I had wondered if a water based product would do better here, or am I just going to have to bight the bullet and switch to a sealer like sikkens?