I have a couple of 65w and with out a thermostat they can get up to 145+, and they work awesome with my herpstat. I use them to maintain ambient temps and they range from 81-84 with it set at 84. I monitor the ranges using acurite thermometers/hygrometer.

Though with my home set at 72, my boaphile and t10 enclosures stay an ambient 81-83 on the cool side if my hot spot uth is set at 90.