I think what Kerning pointed out should ultimately be the deciding factor as the page numbering needs to make sense when it's combined with the other documents. Personally I think I'd use 4 separate documents....
Here's an example of curving into a glass bowl. The tutorial's rather detailed for the method contains complex procedrues.
In Rhino rendering it's more obvious but in Bryce it shines better.
This one is Rhino