I'm in a similar boat to you. I initially looked at tiling our marblesheen pool but after a $25,000 estimate, I looked elsewhere. I had set up two guys to quote a replaster, but neither showed up. I have looked closely at Epotec epoxy and have spoken to them on a few occasions and as much as many (most, it seems) will tell you it's a waste of time, from what I've gathered it depends on preparation, the right product, preparation and preparation. Did I mention preparation? The product you choose needs to be a high build POOL SPECIFIC epoxy with a very high solids percentage (95%+) and UV stabilisation. Preparation is key, in that the surface is 100% sound, clean, degreased and roughened up (marblesheen makes a nice base). I have yet to pull the trigger, but I am close.
The company I will use have said the finish can last anywhere from 5 to 20+ years, depending on myriad factors such as level of usage, traffic, sun exposure, cover usage, floor cleaner use, etc. The surface will slowly degrade with time, that is the nature of epoxies, hence why you want one that is mostly solids, not thinners, and high build. The thicker the film, the longer it will last. Extra coats on the stairs and traffic areas of the pool will help longevity.
I'm expecting 5yrs, for the price that's pretty good in my books, and in 5 years I might have the cash for tiles! Those pearlescent glass tiles look simply amazing!
Speaking of price, as a DIY kit I've been quoted a bit over $2000 for the kit, including primer. I don't think there's a "great" product for anything close to that.
I'll be doing mine in the coming months, so if you can wait, I'll report on the application part at least! I've got a thread in the Construction forum, Pool Refurb in Melbourne.
Cheers!
