Cage or tank for pet snake?

I don't have any adult cages at the moment. I used to keep mostly boas, but certain events occurred, honestly due to pure stupidity, on my/our part, that led to the loss of a number of critters. Which is when I started in on the Indo-Australian pythons, which I had wanted to do anyways. I started with smaller animals, one because they are much less expensive, and two because I rather like watching them grow, especially with these species, as the ontogenetic colour changes are amazing! I also got rid of and/or destroyed most of the old caging I had. So I have a bunch of less than three year old animals at the moment. I'll get some pics of the tank set ups I have, plus my whole rack and the way I have the tubs set up in the near future.

Here is a pic of Monty, a Suriname red tail, Boa constrictor constrictor, when we were moving him into a new larger tub. We hadn't finished setting it up yet...
(Allot of people seem to have a Monty python, so Shana wanted a Monty Boa )