The factors determining the thermodynamics of any given enclosure make up quite a list. The materials it is made from, the positioning and dimensions of each, existence and position of any gaps, the size and positioning of vents, the position of enclosure (e.g. concrete floor vs carpet or elevated, in a bank or side by side, whether there is access to a breeze), the ambient temperatures of the room. Thankfully, by manipulating the heat source and ventilation, we can obtain the temperatures required inside the enclosure.
The most important thing as regards your heat source is to use the minimum wattage required to achieve the desired temperature range. Once you have set it up you can decide if a thermostat is still necessary. What NOT to do is have well over-powered heating held in check with thermostat. If the thermostat were to fail you could likely end up with baked reptiles. They can handle being too cold for some good length of time. However they succumb very quickly to excessive heat.
Those who do not use a thermostat will, if needed, alter the wattage of bulbs or the length of heat cord used in the enclosure, to compensate for temperature changes over the heat of summer versus the cooler months.
Regardless of whether you use a thermostat or not you should purchase a temperature gun and build in using it once a week to check temperature gradients in all enclosures as part of your maintenance routine.
Blue