My D610s work fine with my AI lenses. The only issue was my pre-AI 85mm 1.8, which I AI'd myself and now works well. The DF kinda baffles me. It has the D4 sensor, but is crippled in frame rate to slower than the D610. It uses a 610 processor. Some of the buttons look awkward to use. The front command wheel is vertical so it may need two fingers to adjust, I'd have to try it myself to see. Also be aware that it just comes with one focus screen (matt fresnel I believe). If you want split focus, you'll have either buy an aftermarket one from Taiwan, or try to make one like I did with an FM3 K3 screen.