Quote Originally Posted by neuroanatomist
The short answer is yes, it's a significant step up in image quality.

I knew it! That's what I figured.[]


Quote Originally Posted by neuroanatomist
You may need another lens to cover the 17-24 range, though, as 24mm on a 40D body is 'normal' focal length, not wide angle.

Already have that covered - I use the Tokina 12-24mm f/4 to cover anything wider than 24mm.


Quote Originally Posted by neuroanatomist
You might also consider the EF-S 17-55mm f/2.8 IS USM, which has L lens image quality and preserves the wide end of the focal range

I thought about it, but I could see myself going full frame or APS-H in the future.


Quote Originally Posted by neuroanatomist
If you have another lens to cover that (e.g. a 70-200 L zoom), you'd be set.

That's my plan. As my shooting advances, and the need (and funds) arise for a faster telephoto lens, I can go ahead on a 70-200 2.8 L IS USM. In that case, I would have all focal lengths from 12mm to 200mm covered.