Dmasters, I envy your collection...an R100 cafe racer style would look great in my garage and it would address my love for old bikes. Never owned an airhead and I think it would be refreshing to scoot around on.
Anyway, The C14 is proving its worth to me and it actually does everything pretty well, including two-up as you mentioned. Very surprisingly, I don't mind riding the bike around town and found myself filtering the big bike thru traffic the other morning with ease. What I am really waiting for though is some nice backroads sport touring. This is where I am sure the bike will really shine, especially over the course of multiday rides . I actually caught the missus inspecting the panniers the other day and she noticed the old Givi topcase sitting ready-to-go. She really loves BMW vario cases, but I think the BigBlueSquirt has gotten her attention too. She remarked that while she loves the GS, the "crotch rocket" is very comfortable