If you do get that origin8 frame, be sure to let us know. I've been looking for a vintage mixte for my 6' tall wife for over a year (off and on) and have yet to come up with anything. The 58 cm frame that origin 8 has would probably work (if it's not too big) for my needs. Not ready to drop the cash on a full build yet, but if it turns out to be good, I'll have to look into it further.
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Bikes: 1996 Eddy Merckx Titanium EX, 1989/90 Colnago Super(issimo?) Piu(?), 1990 Concorde Aquila(hit by car while riding), others in build queue "when I get the time"