What I lose with the loss of the 1.6 factor as far as my 300 f/4 L IS goes (and my 135 f/2), I make up with faster AF with the 300 . And because its a very much larger file (12 mb if RAW vs. 7 mb if RAW with 20D) it does allow a great deal of cropping with little or no loss of sharpness. This particular image was very heavily cropped and no sharpening at all in PP. What is also astounding is the viewfinder - bright and large. For my 60 year old eyes, its a boon

.
There is vignetting, of course, with my 17-40 but I am having a lot of fun with the images which come out of the 5D with this now really wide angle lens. This can always be adjusted in
PSCS2.
The young woman seemed to be lost in thought as she sat at the Quay. She had one of those faces which, while not stunning, had a lovely aura about it and to me, much more interesting than most.
Cheers
Sheila