I've been playing around with panos for a while and have decided to get a better head.
My current kit list is,
5D, 1D2n and 20D
Tok 10-17 fish (with hood shaved off), Sigma 15mm fish and Canon 17-40L (plus L lenses up to 300mm)
Frotto 55pro and the 555B levelling column. I have a cheapy L bracket style head that's not even remotely accurate and a 303 head. The frotto is big, heavy, not that friendly and is pretty visible at 10mm.
Logic says that I should do all my stuff with the 5D and the Tok for quick captures of busy scenes, and the other lenses for higher quality.