Erm Not only speeds. Actually the specs for both bike is different. Like example the FD and RD is from different model. If you intend to cycle fast or wana upgrade in future then you choose Fit. Decaf TT i think not much thing can be upgrade. its more for leisure cycling.
thanks for the response. decided to get the decaf. have test ride both, overall better for me is decaf. maybe if i feel the urge to upgrade, i would just sell the decaf and look for faster rides. not really satisfied with my ride on the fit. not fond of the many gears to switch and the frame is a bit mis proportioned. just my opinion