Ah well, 41qt is basically what I would use for any adult female. the 40qt is what I have my oldest male in and I like how it works so far. Although, even a 34qt or so wouldn't be bad for an adult male.
Sorry if it seemed I was being strict on my guidelines for how I house my Balls, it was just to show how I feel about housing Balls of a certain weight and what I usually go by. I believe that they should have some space to be able to move around in even if they do like confined areas. But anyone can do whatever they love and I certainly respect that, just don't think an 800g Ball would look comfortable in such a confined space.
Hope you find what you like best for your new guys, and hoping to see photos of their arrival!