In 2011 I moved into an apartment and took me T-Entertain with VDSL50 as IP port. In April 2013 I moved and have a new IP connection. However, this does not work with Fritzbox Annex J connections, although the serial number is compatible according to the manufacturer.
Follow: Rental equipment of Telekom and a worthless Fritzbox has cost me 215 euros. For me it is clear also because of other experiences that the products of AVM their money are no longer worth it!