This is my favorite lens. works great in combination with the Canon 10-22 and 70-200/f4 L.
The combination of zoom range, 2.8, IS and USM make for a great walk-around lens on my 30D. The IQ is excellent. Colors and sharpness are great. The lens is a little large, esp. with hood in place.
I have seen posts that go on and on about dust problems, but I have seen none (and I live in the desert of Las Vegas - very dusty).
Does what a great lens should do - lets me capture what I'm seeing!