Mine will do the same thing. 16K miles. Tires good. Front alignment just done and rectified a toe in problem on both drivers side wheels. Improved handling characteristics with proper alignment.

OK, this is what I have noticed. After about 8-10 miles or so I no longer detect the random pulling. I say random, because sometimes it is to the left, then could be to the right and sometimes nothing. To me it seems like the brakes need to warm up a bit to be at optimum performance.

Take your CF to a mercedes savvy repair shop and stay away from dealers unless the work is to be covered under warranty. Just my opinion.

I would doubt, very much, there is anything wrong with your CF. As previously mentioned, it is very doubtful the rear brakes are causing this issue, but it wouldn't hurt to get things checked out as I did.