Most versatile walkabout lens for APS-C; excellent image quality from 24 to 85 mm; still good from 17 to 24mm (very good with PP); IS.
Cons:
Nothing much to speak.
I use the lens for 2 years 90% of shooting time. No regrets. There is no one lens without some shortcomings, even among L-grade. Yes, EF-S 17-85 IS a compromise, but finest!