A lot of opinions .....
I worked with 10-22, 11-16, 17-40 on different cameras - mainly landscape photography.
The Tokina is sharp that's true, but I had really flare problems with that lens. Different tests are showing that as well. The barrel distorsion with the 17-40 and the 16-35 on a full frame camera (i.e. 5dmkii) is much higher that a 10-22 with an APS-C (7D) camera. For architecture photography I think the 10-22 is much better.
The canon 14mm is another possiblity. But ... if you prefer to work with filter - another problem.
A good website with lens reviews i can recommend is the german but english speaking photozone.de
If I look for a lens I always testing it by myself.
Good luck ...
