I personally love both of my AP terrariums and I have a T10 on the way!
T8 is fine but it is a little too short. If you have the funds, i'd personally recommend getting the T10. It's going to make your life easier when you clean the enclosure and try to take the snake out. However, since T10 is NOT a quick ship item, you'll be waiting for about two months to get it.
In regards to heat, I recommend investing in a RHP (radient heat panel). Technically, as long as you provide the "correct" ambient temp for your BP, you really don't need a hot spot.
Here's a great sticky on the T8: http://ball-pythons.net/forums/showthread.php?t=165571
And here's my setup (ive been posting it a lot lately):![]()