Well, I just have to click "submit payment" between one of the two: Nikkor 10-24mm, and Tokina 11-16mm. I've decided I'm purchasing one of the two. The Sigma 10-20mm f4-f5.6 was a runner-up in my decision making.
I would really like to be decisive on the matter. I have two options as I see it:
Option #1: Get the nikkor 10-24mm. It is 1mm wider (on DX that's 1.5mm FoV wider, which is ~10% wider). It also is 8mm longer, for whatever that's worth. Stick with DX, get a lens that is fast and handles 30-35mm later this year. I'll have to worry about (and possibly do a few exchanges) due to focus accuracy & no focus adjustment on my D5200.
New Option #2: Same as above, but the Sigma 10-20mm f4-f5.6.
Option #2 (edit - not getting this lens anymore): Get the Tokina 11-16mm. It is $200 cheaper, and functions better on full frame. Instead of sticking with DX, I could switch to full frame instead of getting a 30-35mm lens sometime in the future and continue to use the Tokina 11-16mm. I'll have to worry about focus accuracy right away, but it won't be the biggest deal in the world on a wide angle.
edit: After posting this, I've read so many issues about the Tokina 11-16mm product variation. This thread that I googled up makes me think I shouldn't get it:
http://forum.blackmagicdesign.com/viewtopic.php?f=2&t=3807