I actually sold my 17-40F4L on here for this. I bought the 17-40 for a trip where I knew I would be taking a lot of really wide shots outside. When I got back, I realized that the F4 was a little too slow for what I really needed, and I decided to sell it for 550. With that 550, I bought this lens for 280, a new(used) tripod and a new (used) flash. I think I need to refine my basic skills, especially with flashes, before I justify buying L glass again. And that is my story.