I bought a boaphile enclosure once with the UTH add-on for like $15. I felt ripped off because for that much money I was expecting something more than flexwatt tape. I plugged it in and waited all night, even right against the plastic it never got above 75 degrees. I could feel it was very slightly warmer than the unheated plastic, but not at all a significant change in temperature. Sucked. I don't know if it was wired wrong or what, but I tore it off and switched it with a zoomed heat pad which worked awesome, it was HOT to the touch in just a few minutes. The hot spot on the ground stays at a nice comfortable 95 degrees now. That was fairly pricey though. What kind of heater do you use?