Image quality ok, processing speed underground, remote control WiFi rudimentary.

The P600 was designed as an upgrade to my P510. What to improve the picture quality was also visible in terms that affects at least the contrast and color saturation. The focal length of 1440mm is also sensational and results in bright sunshine (and only because) even from the open hand sharp photos.
The speed of the autofocus is deficient in bad light. It is often inexplicably seemingly the entire focal range pass through, even though the picture on the screen was previously sharply, which takes a few seconds. In good light, the time for the auto focus is acceptable.
For fast sequential shots, the processing speed is absolutely unacceptable. Have 7 photos in my fastest SD card (45MB / s) 29 (neununzwanzig) stopped seconds. During this time, the camera can no longer be operated. They can be safely put down and activate his second camera, or even his mobile phone camera to weiterzufotografieren.
Since even my P510 was much faster.
Even if the fast burst mode, which is enabled by default with me, releases only 1 image, it takes 3-4 seconds until you can shoot another image. As long as the motives often wait not, except perhaps landscapes.
My smartphone is faster here.

The remote control capability via smartphone was a crucial selling point for me. This is only rudimentary trained, ie trigger except image and zoom there is not much.
Manual modes I have not found. Unfortunately, the display is based on the camera when it is operated remotely via WiFi. So I have absolutely no chance for further settings in this mode found - sad.

All my criticisms you have to see, of course, subject to the proviso that I'm just too inexperienced to operate at such a camera.

My suggestion to Nikon: test your own cameras times during development. Give it time, for example, your doorman or your friends, asking the then times what they make of it - then you would certainly also one or the other noticed.

A camera for people who bring time - then you can snap good photos.
For photographers whose motives do not want to wait so patiently - brings you prefer something else.

I have returned my P600 and hope that at any successor, the speed is better.

3 points yet, because the image quality has remained even beyond my expectations.