I've had 4 Exo mats now for going on about 10-12 months now and all are fine. Funny, I have read posts here of UTH's failing with terrible results to the snake and I have read of thermostats failing with the same results. I had a Zoo-Med and that one got REALLY hot without a thermo on it. We have two Exo Tropicals for our RTB due to the fact that he is a burrower.