The answer of course is get both. I own both and love both of them.
Dust has not been a problem with either lens, both of which generally wear good quality filters.
Forget about Full Frame for now. Both lenses have excellent resale value and are easy to resell.
Thanks. I am not planning on FF at this point. Dad has a 5D which is at my disposal.
IQ is not MUCH better from the 24-70. Owned them both. 17-55 is sharper and IQ is on par. Build quality is not on par however. Also there is a vast difference between 17mm and 24mm on a crop.
I've owned the brick. For me, it was just too heavy for a casual walk around lens. Great build though and I liked the IQ produced by it. It just wasn't the perfect match for me.


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