The bottom started flat but over time it has dropped down some sagged. It has dropped about 3/4 of an inch I actually made a support to the centre of the enclosure to help hold it in place. No it did not come with a UTH. It does heat quite efficiently with one however. The PVCx of my sly and boaphile is not as easily heated it needs more heat longer to get the same internal temps.

I have not had too many issues with humidity it is currently in a room that is now (just checked) reading (accurate hygrometers) 39% and the vision is at 61% and I don't recall the last time I misted anything. I have not altered the vision at all. I would be concerned about the low ventilation if I it was farther apart than this!