I took my first ride on my Madone 7.9 / Ultegra Di2 bike Sep 26/12 and today I rolled over 10,000 kms on it. It's a great bike. The Di2 has worked flawlessly, I've only recharged it 2x since getting the bike. The rear brake located at the bottom bracket has created no problems at all, no dirt buildup, never any braking issues. All in all it's been a fantastic ride and rides like new today. It has removed all new bike lust from me and I'm able to read cycling magazines without feeling the need to upgrade my ride.