There's also some good reason to believe that trying to have it adjusted is a losing battle (or at least one not worth fighting) if you get other lenses or cameras, provided you have adequate headroom in the adjustments.
My D800 and D4 are quite different.
The latest example is a 400/F2.8 came in and I shot the D800 first, and it required no adjustment - fine at zero. Put it on a D4 and it required a -20. That was by eye sitting at a baseball game and fiddling with it because my shots were blurry.
So brought it home and did it very carefully multiple times with Focal, and sure enough the peak is around -18. And -1 for the D800.
Huge difference. But I just dial it in and move on. I wouldn't even think of risking shipment (and delay and possibly making it worse) by shipping either lens or (which?) camera back.
In my mind that's what they are for. I see a lot of people who say more or less "if I had to fine tune, I'd send it back and get it adjusted". There seems to be a perception that if fine tune is needed, Nikon's QC failed -- I get the logic. I just don't agree with it.