I have the same dilemma. Last year I set up an old Cannondale for a TT set. I did not like the results and felt a little stretched out. It is a very old Black Lighting 56 center-to-top. I was thinking of switching over to my other (extra) bike; but it is steel. This bike is 53.5 center to center. The Cannondale also has limited rear drop out spacing of 125mm. This limits my wheel choices. I could use lighter wheels with the steel bike.