At the risk of sounding like a smart-arse the most comfortable is the one that suits your own arse. Thus, for me the B17 and Team Pro are just about perfect, with the Pro having the edge, and whilst I had a a Swift it took a long time before I broke it in / got used to it, but it was still not as good as the team pro (for me). However someone else might find the Swift perfect for them. For what it's worth the B17 and Team Pro were comfy from day one, so I'm not personally a believer in the 10,000 miles to break them in malarkey never mind adding various concoctions to break them in quicker.