I will seriously take a close look if I am you, the Tokina 10-17mm , for its flexibility as well as built quality.Like to add that, on its longer end, it does acts a bit like a ultrawide
Image quality from this lens far from being sloppy. So its definitely worth the consideration.
I can't comment too much on the Nikkor 10.5mm as I am not a Nikon user.
But being a owner of both the Tokina 10-17mm and Sigma EX 15mm fisheye(known for being sharp and having good colour rendition) , I would say the quality is very close.