Need some confirmation on frame sizing from all city owners for the thunderdome or big block (same geo). I am 5'9" or 5'8" barefoot and about to order the 49cm. For those of you who have never researched their geometry a 49cm has a 53.5 cm top tube. My 54cm caad10 road bike has a 54.5cm top tube but its a bit big. Had to drop to a 90mm stem. So i think i am making a good choice here but any confirmation or argument against would really help. What size is your frame and how tall are you?