I'm considering a wider option than my 17-55 Nikon zoom. There are days that I have missed the wide perspective of the 20mm that I used to use on my F100. As of now there have been no comprehensive reviews of this lens that I have read. At this point I'm leaning toward a Tokina 11-16 for landscape photography. Most of the time I will still use my 17-55. Why buy the Nikon 10-24 over the Tokina other than the fact that the Tokina is always out of stock?