Having a thermostat on the bulb will regulate how much output the bulb can actually produce, it won't be turning on/off. It will just be regulated. If you do end up getting a different bulb, I would get the darkest night bulb you can as well. You don't want the light shining on your BP all day, that would be a stresser for the snake. BPs will spend the vast majority of their lives hiding, and are nocturnal by nature, so the ambient light in the room is plenty.