I would take a close look at the clearance between the RHP and where the snake can get to. The site I saw said a height of 12" for the vision 221. Let's assume that is internal and not external. If you account for approx 2" for the RHP that leaves 10", if you put a hide in that is 3" tall on top of 1" of substrate your down to 6" of clearance. I believe it is recommended to have 9+ if memory serves. I'm guessing this is why it's recommended for this unit to be a UDH only unit. If the 12" is external you have even less clearance. The surface of my 80W RHP can get over 200F. Not worth the risk to snakes. That's why I built mine with 16" inside height.