I am in the minority as well. I use a 60d with the 24-105, but I also own a Sigma 10-20 for those times I need something wider.

The primary reasons I opted for the 24-105 were the weather sealing and the 56-105 focal lengths. The sealing came in handy on a recent trip to the SW US during monsoon season, and I really like the added length for portraits. For me these benefits outweighed the 17-23 range and the extra stop. I think it's also easier right now to find a screaming deal on the 24-105, and once you factor in a Canon lens hood (supplied with the 24-105 but not with the 17-15) the gap is a bit wider than it appears at suggested retail.


That said, after going through my trip photos I notice a lot of my shots were at 24mm. At the time I didn't feel like I was missing much (I wasn't constantly swapping to the 10-20 etc.) but the numbers suggest that I was trying to go wider with my walkaround lens.

I'd make the same choice now, but again this also includes owning a lens in the 10 to something range.

Good luck.