Well, I got 5 years out of our ultraguard, but I was less impressed than I hoped to be - I expected 10 or more. Ken has now retired but still taking my calls to advise on the resurfacing. There was no offer of any response to Ultraguard's "guarantee" though. The epoxy wore or dissolved away, esp. in the shallow end and on the pool steps. I believe I may have caused this by letting the total alkalinity run unchecked, and creating corrosive water. Anyway, my mortar patches became visible. I had another 3-4 bubles form and break in the epoxy - likely caused by the plaster below. Anyway, I am using Ultraguard again. I will be grinding the hell out of the surface, making as many smoothing repairs as possible and then paying closer attention to my pool chemistry... an expensive and time-consuming lesson. I intend to double up the coating on the shallow end and triple-up on the steps; just in case.