I went with a 40g glass tank for my snake, he definetly doesn't need all of that space. But I figured that one he gets full grown he would be happier and I would to since I won't have to go out and buy a second tank.

The problem with the glass enclosure though is the top of the cage let's all of the hot air out. I also tried to cover up a good portion of it with a towel except for a spot for the heat lamp and to let air escape. That didnt work so I read an interesting idea on this site. Take some aluminum foil, place it reflective side down on the top of the wiremesh top, place down 3 layers, and completely cover the foil with Duct tape. I just did that today and without any extra help the tank has gone up two degrees on its own and it even got colder outside today with all the rain over here.