Quote Originally Posted by Chris White
I do not know how much more IQ difference I would see, but I realize the EF 16-35 f/2.8L USM is better.

Not necessarily. I owned the 17-40 but sold it. Sharpness between the two lenses is the same. Color and contrast were a bit high for my taste on the 17-40, but it could have been just my copy too. I occasionally shoot weddings and since I also own the 24-105 at f/4 I needed a faster wide angle. For most of my wedding shots I was using the ef-s 17-55 f/2.8 on a 40D and it was fine. But I went FF and got a 5D and sold all my ef-s lenses. 5d for low light indoor church shots where flash is forbidden is awesome. I still use the 40D for my sons hockey games with the 70-200 f/2.8L IS. I find this to be a very good combination for what I shoot. If the 17-40 is in your budget get it as you can't go wrong. It is a fine lens. Unless of course you need to shoot indoors under poor lighting conditions.