Picked up my Z7 kit on Wednesday afternoon late and have really had little time to take photos. The kit is thr Z7 + 24-70 f4s and FTZ adaptor. All I have been able to do so far is to set the camera up similarly to how my D850 is set up and play with the AF with the native 24-70 f4s lens and a few of the F mount lenses with the FTZ adaptor. The AF speed is very good, probably as fast as the D810 but not like the lighting fast D850 and I never thought it would be as the D850 is simply a stunning AFing camera. However, the AF like the D810 means that it is still excellent and F mount lenses with the FTZ adaptor work just as well. I must say am very impressed with the AF, much better than I had anticipated. Build quality is excellent, it's a solid little thing and imparts confidence. The camera feels good in the hands and is comfortable to hold and operate, but still getting used to how it works. The good thing is that the menu etc are very much like all Nikons which means it is easy to navigate. The 24-70 lens is sharp, and focuses down to 300mm and thus can be almost like a macro! Overall IQ looks great and similar to the D850 as you would expect as it is similar Mp to the D850 and has the same pedigree.
For me, the Z7 is an adjunct to my D850 not a replacement as the D850 is for my birding and fast action camera. However, the Z7 could basically do everything else and all in a package that is half the weight of the D850 and still be able to use all my Nikon F mount lenses. As a travel camera and general purpose camera, it will fit the bill perfectly. A few months back I was considering a Fuji X-T2 or X-H1 and lenses as a travel alternative and to take on my recent trip to China in order to save weight and room and I asked MissionMan for his thoughts on that system, which he kindly gave some excellent advice - thank you once again, MM. However, Nikon then announced the Z7 and I decided to wait and see what they had to offer and I am glad they did as the Z7 is simply perfect for my requirements and I don't have to buy a new kit of lenses! I ended up taking the D850 and lenses to China and even though it was a heavy and large kit, it paid dividends, the results are excellent.
In a nutshell so far, the Z7 is simply a great little camera and is much better than I had anticipated and will do everything that I was hoping it could do.