I used Durabak last year, Finishes smooth no rough portions, so far no complaints, but i've only had it for half a summer and the winter. I did lots of research and decided to go the durabak way instead of hurc. I would just suggest take your time with prep, and with spraying it on (that was another good thing, it wasn't very thick to spray, but very very sticky when wet) Looks really really good in the spots that weren't rushed, but a storm was rolling in so i rushed towards the end, and where i rushed (didn't allow other coats to fully dry) you could tell, it ran and such. But so far so good. You could probably get away with one gallon as well.