Al I have read a few reptilecare blogs and alot of them I have read think "grow up cages are bunk."
I agree. My 09 BP is doing very well in her 36'" cage even though she is only an 09.
My advice is get and use the rack, double the amount of hides you use and you should be fine. I am not very experienced but I read alot of people had success in this way. And so far it works for me to.