Decsions decisions decisions, and I can't decide - Help...

The recommended alternative to the 24-105 lens is the 24-70 or 24 f/1.4.  The recommended alternative for the 17-40 and 16-35 lenses, for those who can use EF-S lenses, is the 17-55 f/2.8.  The thing that's lacking with the 24-105 is the f/4 relative aperture.  It's nice for landscapes and still-life, but not for everything else, not when you could have f/2.8 or f/1.4 for the same price.  The 17-85 lens, although good and something I just used tonight, is not an "L" lens.  If you want the quality of an "L" lens, you need to buy an "L" lens.  The 17-40 f/4 is highly recommended, depending on what you need it for.

Your stated purposes, unless you plan to get wet and throw around your lens outdoors, suggest that the 17-55 f/2.8 would be a good choice.

http://the-digital-picture.com/Reviews/Canon-EF-S-17-55mm-f-2.8-IS-USM-Lens-Review.aspx

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