The difference between 35mm and 24mm is a lot more than it sounds like. I have the 35L and it's excellent. I made the choice between the two, initially, by setting a zoom covering that range to each focal length for a while, and seeing which I preferred - I found myself wanting to crop most of the 24mm images in post. Still, I ran across a 1 month-old 24L II on CL today for $1100, and I admit, I am sorely tempted...