Wide angle zoom lense selection
I am interested in purchasing a wide zoom lense. I enjoy landscape photography while hiking in the Rockys and as an architect, I have a need for a wide field of view for interior spaces.
I have a Canon XTI (hoping to upgrade). I have been looking at the Sigma 8-16mm and the Sigma 10-20 f3.5 although I am not tied to Sigma. I like to use a linear polarizing light filter in my Cokin P series system for outdoor shots and would like to use it on any new lense if possible. I understand the 8-16mm can not be used with a filter. I assume a filter can be used with the 10-20mm.
Should I be concerned about using/not using a filter with a wide zoom like this?
Given my expected uses for the lense, what advise/opinions do you have regarding the purchase of a wide angle lense?