I've done exhaustive research but still can't decide which way to go for my first lens to use on a 450D. (I have reasons for wanting this body over a used 5D, etc,.) I shoot landscapes, and will eventually go full-frame. I need the IQ and can spring for L glass, but only one lens for now.
I'm not sure the 24-105 f/4 will be wide enough on a crop body--not all my shots are wide, of course, but 38mm is even less than I was getting on my RAW p+s cameras. No question it'd be great on a 5D, and I'd love IS.
Considering the 17-40 f/4L--the price is definitely right, as is the coverage, if too short. Light weight is a definite plus.
I understand the 16-35 II is better glass, but even less range, and twice the price.
Thought about the EF-S 17-55 f/2.8 IS, I think it'd be a great all-purpose, but lack of sealing concerns me, as I wade in creeks and rivers. Can't use it on my (future) full-frame, either.
Your shared experience would be greatly appreciated... 

