I had a very good shop owner/rider/racer build up my bike. I finally understood how much there was to a real fit. He fiddled with the saddle, the bars on and on.

Did these guys try to fit you onto the bike? adjust the saddle? head set? Plus vibration has to do with tires..the bigger the better for a ride and I'm told, too great fork stiffness means vibration.

Maybe you need to go back and demand that they adjust it for greater comfort? or maybe they're hopelessly lazy for being the only game in town?