Obviously I agree, and certainly the AF motors do seem to be essentially identical. (They might even be the same part, I have no idea.) But one thing that might be different is AF lock on speed, particularly in low light. That would be due to the AF processors, not the AF motor, but it *might* show up as a difference between the bodies, and it would apply to AFS lenses as well as to screwdriver lenses. But it's at least a possibility. The D4 in particular is rated to lower light AF than the others, so it may be quicker than D3/D700. I'd guess the D800 to be similar to or equal to the D4, but I don't know.
_____ Brian... a bicoastal Nikonian and Team Member
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