I've had the Mercedes Me on my 2012 CLS for some time, I bought the Mercedes adapter off ebay from Germany and then just went to the dealer to activate it, anyone with an adapter was able to activate from March 2016 but this was kept quiet lol. I did suffer crashes, lags and problems because of compatibility :-(
I am a bit disappointed with the features, it would have been good if they could at least have engine oil, Tyre pressure monitoring and brake lining which doesn't require anything and is possible because they do it with the star diagnostic equipment through ODB. Oh well all we can do is wait I guess :-(