I've recently come to some conclusions about the relationship between weight and the abilty to inflate one's belly. The overall size of my belly was larger when I was heavier. However, I've found that I can hold more air when I'm skinnier. This creates a much more pleasing result. For one thing, my belly looks much larger in relation to the rest of my body. It's a pretty big contrast; I pretty much look pregnant. For another thing, the shape is much nicer. It's much rounder than it ever was before. It's also very tight - I can feel the skin around my belly tightening as I do it. I think my belly button is even stretched a bit.
Anyway, it's pretty awesome. Just thought I would share.