The AF sits in this copy perfectly, ie front or back focus I could see over the whole focal length does not, he is really very fast, accurate and quiet. The processing of the lens is really great (because Nikon could in many a lens to take an example) and the weight is very pleasant.
The image quality is in my opinion between my 40mm Macro Nikkor (almost unbeatable sharply Aperture 2.8 and so far my previous Always plan) and the Nikon kit lenses 18-55 and 18-105, the Sigma is clearly better at full aperture - as opposed to the Kit lenses that bring only from Aperture 6.7 / 8 a reasonable and usable pictures into focus. Of course, the Sigma is with Aperture 2.8-4 not exactly the brightest, but has over the kit lenses anyway a head start and advantage.
But what a no-go for me, are the Lens Flares in backlight. Since I am a lot in nature and in the mountains and go mainly or much scenery photograph, (and the sun would incorporate into the picture) are not to be used as large flares. To photograph With 17-35mm against the sunlight produces large, green lens flares, which are to touch up afterwards with Photoshop or similar not, little or a lot of effort.
CONCLUSION:
The value for money is certainly very good and for portraits and close-ups is also the lens definitely worth a purchase is worth it but not really to use for my sphere of use of landscape photography. Too bad, because otherwise, it provides for a standard zoom lens ensure a good to very good image quality.
