Thought so....
And OP, I think investing in a RHP is the best way to go. The enclosure will do a great job of insulating the heat and the RHP will be the most economical to run while providing consistent accurate temps for you.
You won't need to run any belly heat and maintaining a proper gradient.
Definitely talk to Bob at Pro Products. Make sure you have as many details about the enclosure as possible, as well as avg temps in the room the enclosure is in, etc.. This way he can guide you to the right size RHP for your setup.