I built flat bar bikes on road frames for both my wife and me because we wanted the lighter weight and better feel of a quality frame, something not available on most fitness/commuter/hybrid bikes. I also used higher-level components.
The result are two bike we love. I am not a weight weenie (anymore) but my Curtlo comes in at 23 lbs riding weight with pump, saddle bag & tools, AND a Brooks Flyer saddle; try getting that in a hybrid...
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Today, I believe my jurisdiction ends here...