I *love* that cage!! Definately something I will have to look into when I eventually get a boa (and it gets big enough). If you were building them, I'd be interested for sure!
Lost already beat me to it, but how big are the snakes that you put in there? It looks like they go in there fairly young b/c the size of the hides and the shelves. Can they still fit on those shelves when they are older and bigger?