In my opinion I think it depends on the personality of the snake. For example my male when I got him was put in a vision v211 which is about half of a t8 and he was always trying to find away to get out and every time I opened the door tried to sneak through. A month ago I moved him to a v400, which is about the size of a t8, and he is happier. Doing the exact opposite of what he was doing in the smaller cage. A lot of people will probably disagree with me about him being happier but I don't think anyone knows my snake like I do. But he is eating good now and not worrying about trying to escape, he loves slithering on his branch and getting on top of his hide to catch some rays from the rhp I just installed a few days ago. The reason I say most people will disagree with me is bc he is only 32 inches long and just under 500 grams and 10 months old. If you buy baby bps you don't need to by 2 right now. You can wait until they grow and then you can decide if you need another.