Im trying to decide on a 17" or 19" Big unit. It looks like they dropped the 18" size. Im 5'-9.5" with short legs about 30" inseam. Im a bigger guy but muscular and in shape around 220lb. My current ride is a trek 69er single speed 17.5 with a 100mm stem it feels a tad short to me im always on the back edge of the saddle but other than that perfect.