I've had this lens for about 3 years now and ended up using it MUCH more than I thought I would. It's fun to play with and add visual interest, especially in all the little environments I seem to be in. The good thing about this lens is that it's a lot cheaper than buying a 14-24 2.8 Nikkor, but it certainly shows. The construction feels very "plastic" because it is, even though it makes it very light. However, it doesn't take much damage and certainly doesn't feel very durable - it looks like a whale lens. Autofocus is also quite noisy and can be sluggish, but with such a wide aperture it's not a big deal. The lens has more chromatic aberration than most of my other lenses. I may have gotten a slightly wrong copy, but I guess other reviewers might not be that picky. Of course there is distortion at the broad end, but I enjoyed using this effect and it doesn't bother me much. Overall, this is a decent lens, but I really should have saved up a bit more and gone with the Sigma. I don't have much experience with it, but overall it seems more reliable with better autofocus (and I'm guessing better optics, but don't get me wrong).
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