The 5 YO roof on my Coleman is starting to show black across the trusses, which is the coating wearing off. Last fall when I washed and protected the roof I tried scrubbing to see if it was on top or ...
I used Heng's last year on my now 15 year old rubber roof. It was inexpensive and easy to work with. Prep work took longer than actual application. I don't know how well it's going to last yet.