So I've been battling over which lens would offer the best IQ for my camera (Canon T3i). Gave up the kit lens and bought the 24-105L since it had the range I was looking for and I could pop my L lens cherry. It was a great lens and took some great pics however the f/4 on it made low light situations impossible without the use of a flash. So, as of yesterday, I pawned off the 24-105L and bought a 17-55 IS USM lens instead. The f/2.8 on that should help out greatly for lowlight but at the disadvantage of losing a lot of range from the 24-105 lens. As I have a crop body, I figured the 17-55 would be best suited for that, not that the 24-105 was a slouch or anything. I also have the 10-22 and, most likely, will pick up the 55-250 MKII lens as well so sorta make up for the loss in range. That trio of lenses should pretty much cover anything I need shooting wise so I think that's the way to go for me. I think it's a good choice for me however the thought of parting with a L lens makes me think it might not have been such a good idea. Parting with a L lens seems almost blasphemous. Any of you out there have any experience with the 17-55? I'm getting the lens tomorrow so I'll know for sure if this was a good choice or not. Just needed to see if anyone else out there did something similar.