Good find, Matt! I think the size: 36 x 18 x 15 is great! 648 sq inches as compared with Tommy's (24 x 18 = ) 432 sq inches. I also like the "short" height. Seems like enough height to me.
You might consider heating it with Flexwatt Heat Tape (post #44 you know where). I have never used that, but I think you could figure it out.
A 100 wattage CHE could be enough air heat...hard to say for sure. Might add a second smaller dome (on a rheostat) right next to the CHE fixture with a low wattage incandescent to simulate daylight at least in the winter (?) or a Hagen/Exo Terra Night Glo moonlight bulb on from 10 PM to 6 AM for night viewing plus supplemental heat.
Some Fluker Farms domes have a dimmer function inline on the cord.