My wife and I both used the 200-500 with D500's and later with D850's. To me its the best value in a long Nikon lens and they produced some wonderful images. That said we now have the 500pf's, though not as versatile as a zoom we shoot at 500mm most of the time anyway. The focus and tracking on the PF is much better and quicker as well. I have a 500f4 FL ED VR and it is another step up, particularly with a 1.4 tel. What I have come to find, particularly at altitude the 500f4 is heavy even though it weighs just 6.5lbs. Add a gripped D850 with its heavy battery and its quite a load to carry any distance. I find myself using the 500pf lens more and more vs the f4 except for short walking distance tripod work.