Suggestions for a good UTH / Thermostat Combo

[Jughead915]

I need suggestions for a good UTH / Thermostat combo. On/Off or Progressive? I'm using a 15 gallon Terra Blue Professional tank. I'm told that an UTH should provide all the heat I need for the tank, but I'm not sure if that's correct or not. Does anyone think I'd need a heat lamp as well? Also, with using an UTH with a glass tank, do you need to use a reptile carpet under the substrate? Not sure if the heater would cause damage to the ball if he decides to burrow near the glass.

Thanks!