I'm not one to build a bike I won't ride, so with my shallow pockets if I'm going to spend the duckets to finish a bike it's got to fit my 6'1" lard butt frame, so OS is limited to 24's and 26's for me- no more 18" TT's. Got a mid school 20 I'll ride when it's in one piece, but it's come apart more often than they are together. And of course the obligatory frames in the 'to-do' pile...