This lens is very pleasant to use, its engine rather fast, quiet, and perfect for my various uses. It is mounted on a Nikon D800 unforgiving objectives "bottle ass" and I have very little to say about his few "minor losses", which amount to a dive a little more "soft" and vignetting with larger openings. This view is a perfect alternative to much more expensive Nikkor 24-70 2.8 which in addition is not stabilisé.A about stabilization: this is especially valuable during night photo shooting and concert photos. Finally, solidity question: the lens looks pretty well built, its weight gives somewhat confident (almost 1Kg anyway) and it seems rather well insulated (unlike competitor zoom Sigma) at anti seals dusty episodes.
I recommend this lens to be much more powerful than its older counterpart from Sigma, and at a much better price / quality than its equivalent in Nikkor.