Originally Posted by wahoonc
I know several people, including racers that have gone almost exclusively to Bike Fridays, admittedly they are not (with the exception of the Tikit) a folding bike, but they have the performance, comfort and fit level of a full sized bike.
I agree that BF's are top-notch. However:
1) A BF is significantly more expensive than a comparably spec'ed 700c bike.
2) Drivetrain choices are a bit limited for BF's. (E.g. double and triple front train rings don't work very well; a standard cassette might not work well either, so you have to go Capreo etc.)
3) BF's generally don't fold as well as other folding bikes. (They pack better than they fold.)
4) The drivetrain is usually lower, making it less capable for dirt, gravel and mild off-road than 700c bikes.
5) You can't get a carbon fiber Bike Friday (if that matters to you).
6) They are not as stiff as 700c (if that matters to you).
I can't specifically discuss comfort, since it depends on numerous factors -- tire choice, rim and spoke setup, tire psi, frame tube shapes and design, saddle, expectatons. But I find it a bit tough to believe that a steel 700c bike with a comparable setup to a BF won't give you a smoother ride.
Again, in many situations a BF is more than worth the compromise(s). In others, not so much.