Brian, from personal experience I can say that Watkins, the MAKERS of Hot Springs and Tiger River Spas, do stand behind their products, sometimes above and beyond.
My Tiger River Spa showed signs of heavy oxidization on the shell after 4 years, and my local dealer was trying to argue with me that I wasn't cleaning my tub. I directly emailed Watkins asking for a good way to remove or restore the oxidized surface, and they instead called me by phone and arranged to replace my tub with a brand new one (same model, color of my choice)delivered and set up, at no cost. They were under no obligation to do so (almost all tub warranties do NOT cover oxidization of the shell, period), but they went the extra mile without my asking or expecting it.
Without reservation, I would highly recommend their products and service. Keep them in mind.