I understand that you have made your decision. I am new here and just saw the thread. For anyone who views this thread, I have an alternate opinion. I chose a Sony RX10IV, which is a crop sensor and has the equivalent of a 28x600 mm lens. It is truly a remarkable camera and I use it strictly for nature and wildlife shooting. I recently purchased an A7RIII, with a 55mm f/1.8 ZA lens and a 16x35mm f2.8 G lens for travel, street and night photos. Total cost of cameras and lenses was about $4,400. However, the real benefit was that every time I went out to shoot, I did not feel like I had to carry around a dumbbell. I sold my Nikon D500 and D850 plus 6 lenses including a 200-500mm long lens. When attached to my D500, weight was more than 8lbs. Got to old for that kind of workout. the Rx10iv weighs about 2.5 lbs and the images are every bit as good as the d500 with the 200-500. Just an alternative that works for me.