I rented a 10-22, and thought it's optics were better than my 18-55, so considered it. However, I want something the 18-55 range offers, which comes within reach of the quality my USM primes I have. 17-55 is an option, but I think it's expensive for what if offers, and the tamron 17-50 does similar for half. The focal range is the biggest appeal to me for the 15-85...I just can't see too much difference to it and the pictures I get from my 18-55 on the 7D. Hmm. Maybe I need a rent?
Ray33 - lol. Photos in this thread are superb. I'm just pixel picking to see if the investment makes sense to me.