Autofocus is available only with cameras that offer f/8 support. These include the D4/D4S, D800/D800E, D600/ D610 and D7100.
Have you looked at getting a Nikon 300mm f/2.8 II and using that with converters?
Ordinarily Joe, I would say that's a good option as the 300 2.8 is great at image quality and the use of TC's would give a degree of flexibility BUT if the O/P is shooting wildlife then I'm thinking reach is going to be an important factor that can be improved on with the 400mm ... or even the 500mm for a bit more cash ... 400 + 1.7 gives 650mm and excellent image quality.
But now i'm a bit concerned about the comment of not very good image quality at the 400 end.
Just to clarify it isn't "at the 400 end", that image quality fails with the 200-400, it's when shooting a distant subject that it fails - so a near subject will be fine throughout the range from 200mm to 400mm but it's when the subject is much farther away from the lens that image quality suffers.
I can't say I have noticed any iq issues, the af is quick, and many photos really seem to 'pop'. I use it mainly with a Nikon d3. Not in a position to put up photos at present but you can look on my Flickr, bbr1245, the snetterton shots are nearly all with the 200_400.Thanks BBR. Why do you love it do you have sharpness issues? Can you put up some photos you have taken with the lens? Ive been looking into it and it does seem to be well documented that there are issues present over distance..
But at what distance would you suggest the issues start?