Here is a pic of my Rhino liner that allowed moisture to penetrate and rust the tub. I caught it in time. They also did a very poor job of prepping the surface before spraying the liner. It lasted about 10 years. A few moves later and I lost the receipt so they did not stand behind their lifetime warranty even when it wasn't prepped properly.
I'd stay away from Rhino. They were good back in the day but there are much better products out now. The Rhino was a pain to get out.
Here is the new stuff. It has sound deadening qualities so I sprayed the inside of the hardtop as well as the firewall with the rest of the tub.