I did not like - as some reviewers earlier - that the settings of the old box can not be transferred to the new, but have to be manually re-established.
But that's to make quite. I have to first provide the new box via cable direct connection from the PC with a fixed IP, and then connected to the old box. Thus it was possible, with multiple browser tabs to access simultaneously to both boxing and to transfer a lot of settings simply by copying and pasting.
ATTENTION: with this procedure please NOT the automatic firmware update trigger, because the mechanism is obviously disturbed by 2 existing boxes of different types (at this time is indeed the old box nor that manufactures the Internet). For me this meant that the new box could not get in the update, was no longer available and only after the recovery tool (in the \ Software \ folder of AVM CD x_misc) again had to be re-flashed (and could).
The new box works since then except for one very good and also the previously occasional, unmotivated Reboots the old box were previously only once in the 4 weeks on, where I operate so far. The connection quality of the broadband connection (18Mb) is very good, much better than the old box (faster connection negotiation and also more stable, with less COEs and CPEs).
The exception, however, relates to the DECT module:
2 is booked handsets (1 Senior T-Sinus 45K and a new Fritz! Fon MT-F) have enormous problems with this box (both worked on the old 7270 properly).
The MT-F had only to register with, as long as the pin was in the box to the default setting. The T-Sinus did not have this problem.
The voice quality is with two handsets underground: very common distortion to total incomprehensibility (in both directions), strong noise (cracking, crackling), often complete misfire, rarely even disconnections (the handsets "hang up").
These problems are completely independent of the distance to the box (within the DECT range, which incidentally is also significantly worse than in the old box).
Should also be noted that the new box will be operated in exactly the same environment as the old. It must therefore be assumed that a defect in the DECT module and the control.
A recent inquiry carried out at the AVM support has not given any results and I strongly suspect that a switch of the appliance is pending.
Luckily I have the old box and will not then have to re-operate.
Apart from these problems, I'm quite happy with the Fritz! Box 7390 and it can to remedy the fault certainly recommend.
However, it should be noted that the problems described - at least according to Internet research -. Anything but isolated cases are.
Here AVM has probably still some way to the quality assurance ...