I currently have a 17-35 AFS. I shoot mainly landscapes~sunrises-sunsets with it. The 17mm end always seems to wide and on wide shots at tghe oces, you definetly pick up the curvature from the lens (yes I know that I can straighten it in photoshop and NC). How does the 28 1.4D fare as a landscape lens and all around...is it more versatile than the 17-35 due to it's lower light abilities? Opinions?