Yongnuo YN-685-Nikon: You get what you pay for

Up front, I like the simple manual Yongnuo flashes because of their reliable radio trigger, that gives me a lot of freedom and a simple solution to light up areas. My Elinchrom flashes are much more powerful, but also a lot heavier and need a power supply, so a lot of work to do. Often 4-6 Yongnuo flashes will be enough like the example below of a wooden ceiling in a church shows.

In such a setup I did not use my Nikon Sb-900 very often because I can not control their output like the Yongnuo flashes. The CLS System from Nikon is not alternative to me as it is ir-flash based and very unreliable, only working well in short distances, like with the macro flash Sr-200.

So I sold my two SB-900 and bought two YN-685 instead. These flashes are TTL- flashes and have also a radio receiver built in. Sadly after a few uses I got into problems. First the flashes seem to have a connection problem, often they do not get the information from the camera properly via the hot shoe. So they will fire, but with wrong output and the zoom reflector does not correspond to the lens. 
As a radio slave they work without problems and also as manual flash. But for that purpose I have the cheaper YN-560-III

So if you want TTL flash for Nikon look somewhere else. Metz flashes might be a good alternative or the Nikon SB-700 is not too expensive. 
See also the picture below about the poor quality of the battery compartment of the YN-685, which wont close properly after a few uses.

There is a newer firmware out there, but updating is avery complex procedure and you need a YN622C-TX trigger to do this.