The same is true of the 24-70 2.8 VR
This person is just going by MTF charts and specifications and a little speculation too. But all that is admitted in the reviews.
Personally, I like the MTF chart as a measurement of optical quality. Truth is, it is the only real measure anyway. All other tests involve including the camera and then it is more of a system test, not a lens test. At least when comparing Canon to Nikon. Within the same system, a single body can be used to compare output.
The charts provided by the manufacturers are very close, almost identical to what independent testers find when conducting the same tests. So they seem fairly trustworthy. I find this more helpful than going by RAW image comparisons. There's just too many variables involved in photography that one blogger can make a lens and camera combo look world-class, the other can make it look mediocre.
The way I use RAW image comparisons is to collect many images from several testers and build a consensus opinion. That is, when I can't test the stuff myself. Even then, I still like to compare to others, since individual samples can vary too. Not all bodies and lenses of the same model are exactly the same. I can't test 4-5 24-70 2.8's in a row to eliminate the possibility that one is flawed.
If the 200-500 is reasonable on image quality, it will be a big hit. I'm not expecting miracles here for the price point. Especially from Nikon. Nikon has tremendous value in their bodies, but their glass is, in my opinion, over priced.
