j'avais résumé sur un autre poste les conclusions des tests du 10-22 :

bobatkins : "So my final conclusion is that while you can get a cheaper lens, you can't really get a better superwide zoom for Canon 1.6x DSLRs"
ken rockwell "This is a great lens. It's so great it makes me want to swap over to Canon from Nikon, because it's better than my favorite Nikon 12 - 24 mm lens."
Luminous L : "This lens is capable of producing some very fine results in terms of prints. I wouldn't hesitate to use the Canon 10-22mm for any professional application.
photozone : "The Canon EF-S 10-22mm f/3.5-4.5 USM is a very sound package thanks to a combination of very decent build quality and very good if not impressive optical results"
Digital picture : "I just wish I could use it on my full-frame DSLR bodies."
Juza : "The Canon is overall the best in terms of image quality, but it wins by a slight margin and it is the most expensive of the five lenses tested."

moi, ça m'a suffit, si je dois prendre un UGA, c'est le Canon.