Only limited use ... but usable

The menus are almost self-explanatory for people with a more than rudimentary knowledge router.

The use of the cable modem part is no problem with me. You can query some system messages and draw his own conclusions. If - like me - initially are problems because there is no answer, there is hardly help. One saw only "Downstream frequency found" and ca 45s later "Search Downstremfrequenz". Not helpful. (Solution by the way: KD took over 1 week for internal activation ...; a "no valid account" or something would have been better.)

FOR purchaser (buyer) of a box, which then, for example, to register with KD, the following text from the support is recommended:
>> Can I make a NOT FOR KD acquired Fritz! Box 6360 or
>> Use on KDDeutschland Fritz! Box 7270 port?

>> Purpose of Use KD available Homeboxes Fritz! Box 6360
>> And Fritz! Box 7270 are for the KDDeutschland network optimized
>> Equipment. The devices are not commercially available in this form.

>> You can download a commercially available Fritz! Box in principle
Operate as a wireless router behind a cable modem >> z. B.. A
>> Configuration of cable Germany telephony services on a
But >> not acquired with cable Germany Fritz! Box is not possible.

The box is so even when buying THIRD no bad investment; it's just minor restrictions.
AND you should know before!

The wireless part of work for me too smoothly, because I sit with a smartphone and a tablet PC on the quasi antenna. Why both: Synchronize only 65MB / s, I do not know, because all three devices dominate 802N.
* Update: Google forms! The chips in tablet + smartphone use among others just a 20Mhz wide transmission band, only these 65 Mbit / s go so technically. So it is not on the box. My Philips TV connects with at least 150MBit / s. *

The DECT part was now taken from me tomorrow with a Gigaset C1 within one minute in operation. The C1 showed after entering the chosen for the Fritzbox DECT Base Pin once the date and time correctly. A short phone call revealed in the first few seconds an echo effect, which then but disappeared. A caller complained a low setting and a dull tone. I noticed a crackle on the line.
The Log of a Gigaset 3000 Comfort also ran smoothly. The voice quality was however much better; comparable loud interlocutor almost to the ISDN fixed network unit.

A device attached to a week before more than 8 years old Ascom Eurit40ISDN telephone at the Fritz box runs flawlessly and with impressive voice quality since. No comparison with the C1. The ISDN emulation of Fitzbox is not conspicuous.

In short:
Since the box on KD port is unlocked, they replaced (with me !!, who has rented it) cable modem, router and DECT station.
I would still be 3-star satisfied even without the cable modem part ;-)

If I have to add or change something, then please just post. I watch the responses to them for a while.