I know of those cages that you are referring to, and honestly, I don't think they are appropriate for a ball python. Simply not enough floor space and it will take some tweaking to get the heating right. Those cages are great for displays, however, a ball python is by far a display animal. They will hide all day, and when you go to sleep at night, they'll crawl all over and rearrange the decorations you took so much time to put together.

You could set up a tub, which is less aesthetically pleasing, but would serve the snakes needs more efficiently. If you are set on that exact cage, I would reconsider purchasing a ball python for it, and instead look into some types of geckos or other arboreal lizards.

All in all, spending $100+ for a cage with an 18x18" square for the snake to live in is not, in my opinion, the best way to set up a ball python. When I got my first ball python, I too wanted a nice natural display. I quickly learned that ball pythons just weren't a "match" for those types of setups and turned toward more efficient methods of housing. Since then, my small collection is thriving in their plastic enclosures and I wouldn't do it any other way.