Free at last the phone :)

Log in at the base station and call:
Logging via DECT worked like a charm immediately both at the base station of the Gigaset SL400 and on a Fritz box with DECT function. In both cases, the clip is recognized as handset and calls can be answered easily.
In the case of the SL410 and the originating calls works without problems. The L410 even has no dial pad and thus you can of course there also initiate any outgoing call. It is however very simple where you choose with its existing handset and then transfers the call to the L410 touch of a button.
When registering at the Fritz box I unfortunately do not get - outgoing calls were (me) there impossible.

Voice quality and comfort:
All I can say is excellent.
The clip is simply "clipped" to the shirt collar or sweater - my worry was that one must always speak frantically toward the clip now, so one of the interlocutors can understand well. But this is not so - you can completely move freely and quickly forget (also because of the low weight) that you even wearing a clip.
Both the caller and the called party can understand super. The noise reduction seems to be working great. Only the speaker could be a bit louder.

Application:
In my view, the clip is ideal for heavy users, the way want to do something else than to hold the phone. I use the clip in particular professionally for conference calls, when I casually will write there or document on the computer a little - at last one has it hands free. Note, however, that the clip as opposed to a headset does not work with a speaker and a headphone - so who does not want others to hear, is not well served by the clip.

Improvement:
As I said the speaker might still be a bit louder.
For version 2, I would like to see at least a couple of favorites can be called directly from the clip.

In sum, I find the clip very well. I know of no comparable product. If the potential for improvement to be implemented, I buy also like the successor :)