The overhead heat bulbs tend to dryout air. The best is to have the room temp controled and a belly heat UTH on a thermostat for a hot spot.

That is not practical for everyone so do what works best for you.

I would use belly heat and then use the heatlamp for minimal temp increases so as not to dry out air too much. Experiment and ask others who use similar setups for best results.

I keep my snake room temp and humidity controled and belly heat for a hot spot.