I MUST be doing something wrong

I think there are a bit more problems related to QC recently (possibly related to the adverse conditions you mention), but likely less than one may gather from reading internet forums, where more vocal people tend to participate in. People forget the banding in the D200 and other real problems that Nikon had in past bodies. I have been on the lucky side of the fence as well since 2007, 3 bodies and a few lenses. I'm not picky though, now and then I see a little problem, I understand cameras are electronic gadgets these days, all of them show glitches in performance that are hard to understand, just like your smartphone or tablet.

Except for the lateral assymetry of the focus in the D800, I think the other recent problems, like oil/dust in the D600 (if after a few clean-ups, as seems to be the case of the D600, it goes away), are not that serious. I recall that many early adopters of the D7000 also had a similar (but less prevalent or intense) issue with dust/oil. Mine, bought 8mos after launch, is as clean as on the first day, after many lens changes and 10K images later. I'm actually amazed by that, since the D80 showed dust bunnies now and then, not yet with the D7000.

The D7000's AF was claimed by many as faulty, independent testing (including Mansurov and Thom) showed no issue at all. Even I thought it had some issues, then I realized it has a slight different design compared to the D80, with larger AF sensors. That's better for tracking but may cause problems if one is focusing on a smaller target and there is a higher contrast area behind it. Many claimed that caused "back-focus", but actually the camera just locked behind the desired area, not really a back-focus issue technically or design or QC.

OTOH, I think Nikon is a little behind now compared to canon re PDAF design. Canon seems to have developed a better system that can read lens info and really make PDAF as close to CDAF as possible, no small feat. That's only for the newer upper FF bodies and the newer lenses, but likely will be adopted for the whole line-up. Nikon's PDAF systems are basically 6 years old now, the same D3/D300 system with some updates (D800 and D4 a re more accurate, at least the central point, than D3s and D700), but Cicala's results show slight more accuracy variation than the latest Canons+lenses. So, some work to be done, which is good for us users.

But overall I'm quite happy with Nikon, just a couple of recent images from my daughter's ballet school presentation in december, lowly D7000+70-300VR:

And the "star":

Cheers and happy 2013!

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Renato. http://www.flickr.com/photos/rhlpedrosa/ OnExposure member http://www.onexposure.net/ Good shooting and good luck (after Ed Murrow)