The only spot in the tank that it was hot was directly on top of the UTH, its not like the entire tank was like that. Just an 8x6 inch rectangle (estimating the size). No danger of him overheating. I've removed the UTH for now. When I can find one with a thermostat maybe I'll try again.

For now I'm sticking with the lamp(s) and will deal with humidity issues if they arise.

As far as being cheaper, I have far bigger wastes of electricity in my house, 2 kids that apparently don't realize things can be turned off not just on. Its a novel concept I know.