I saw a camper this past winter at a park where I was hosting. He had a spray on roof done a couple of years previous. He said it hadn't been touched since even for any cleaning. It looked good, but a bit dirty. Who knows how long it will last. I still wonder about caulking around the edges and where roof mounted stuff sits.
2006 GMC 2500HD CCSB 4x4 Duramax/Allison, Titan 52 gallon fuel tank, Prodigy Controller, B&W Companion Hitch
2010 Jayco Designer 35RLTS, Cummins/Onan RV QG 5500 EVAP, Progressive Industries EMS-PT50C, TST Systems 507 TPMS, RV Flex Armor Roof