I got to ride Dura Ace Di2 with electric shifting yesterday, and thought people would be interested in some first impressions. I only rode it for about 5 minutes. It was a reps bike, and the weather was cold (30), so I didn't want to be out to long. The shapes of the shifters fit me well, and the placement of the shifting controls was similar to 7800, so it was intuitive (even for me, a Campy guy). The shifting didn't seem quite as smooth as 7800-7900, I am not at all saying that the shifts didn't feel precise, if felt more like Campy Record the way the derailleur popped the shifts off than other Dura Ace I have ridden. . My favorite part of the system is that as you shift the gears across the cassette, the front derailleur automatically trims itself.. The cranks and brakes were very nice as well, and I believe shared with 7900. Setup was explained and seemed easy enough to do. The group is cool and innovative, but retailing at close to $5k I guess it should be!!!