I'm heading out to Arches in 44 days and have debated whether to say WTH and pick up this lens. I've been using the 17-40L and have been most pleased with it especially in the South West.
I'm going to be shooting at f/16 - f/22 so the faster aperture is not a big deal to me (2.8-4.0).
Is it worth getting this lens, i.e., am I going to notice a big difference in sharpness?
Michael,
I really like my 16-35 II, but that might be largely due to the fact that the 17-40 that I had before it was an absolute dog. I'm assuming that you've done some testing with the 17-40 and the 5D II; if you're pleased with the results, there's no need to go with the added expense and weight of the 16-35. I used my 17-40's cruddy performance, and the fact that I am also pursuing a masters degree in photojournalism, as the principle excuses for shelling out for the f/2.8.
Oh, and I forgot to mention: another reason to stick with your 17-40 is that you can then (possibly) justify a purchase of the new Zeiss 21mm Distagon in Canon EF mount (manual focus but with focus confirmation) that is coming out later this year with an MSRP of $1800!!!