I only purchase Dura Ace ST 7800 brifters for doubles and only Dura Ace 7800Rear Derailleurs, Front Derailleurs, Brakes, bottom brackets and crankset. I have a road bike projects, I sadly won't spend money on Dura Ace 7900, 9000, 9100 and 9200 because more fragile, more difficult to repair and...