AVM is well known for reliable products and innovative technology. Data transmission over power lines also works (Powerline Lmapen lit, but the adapter devices hang in between for no apparent reason sometimes and must be removed and turned back on. What is the reason could not be clarified yet. Current side everything is OK. Also, what the phase balance is concerned. But when it is the data transfer function really great. In this respect, there are only three points, because I'm not sure really 100% of it.
Update on 20/05/2014 So I can not take in the stable operation of the adapter. Now I have my Fritz box 7390 used as a repeater and can thus now live outstanding. But the powerline adapters are very special. I guess on a functional test of the adapter (in their own power grid at home) can not get one. For me it has just "time" works and then "time" not again.