I have the Canon 7D plus the 10-22mm EF-S and the Canon 5D II plus the 16-35mm EF II.


You might think that you would get a notably better image from the 5D II/16-35mm combo but really, although it is somewhat better, it is not that significant. Only in the corners do you see sharper definition with the 5D II/16-35mm and even then it's not overwhelmingly sharper. I find that the 10-22mm is more flare resistant than the 16-35mm and that can be important too. So I continue to use both. The main advantage of the 16-35mm is the f/2.8 aperture.