Ok, I'm back with a lens comparison question. Hannukah is around the corner, and I still owe myself something nice from the last time. I've asked plenty of questions about the 70-200 products, and have decided the only relevant one for me is the new 4.0 IS. But I've bumped into a different lens, called the 70-300 DO. Below are the links: EF70-200mm f/4L IS USM vs. EF 70-300mm f/4.5-5.6 DO IS The 70-300 may not be quite as sharp, but it has a good speed and some good range. I like shooting in cities, so the shorter 70-300 might actually be easier to carry around. I enjoy long exposures with tripods at night, and sharpness DOES matter for those kinds of images. Who's got experience with the 70-300 DO, and who has comments in general? Is there a third-party manufacturer that I should be seriously considering?