Trek Madone RSL Di2 9100 Fits the Di2 perfectly, I am 100% satisfied. The front derailleur shifts better. I have no noises except when crosschaining, but I also had that with the Dura Ace. It is said that because of the holes in the outer and inner plates, the front derailleur tends to stretch a little faster. But it has less weight. I was sceptical at first, but I am very satisfied with this chain.
If you want a Light weight good looking chain look no further, these KMC chains are strong and long lasting.