I just got my 10-22 from a local photography shop this weekend. I haven't tried using it outside but I took shots of our dogs, and it's razor sharp! I was a bit skeptical on getting one of these EF-S since I got a 24-70L two years ago (and my, it's also sharp). I guess this wasn't a bad idea to grab a superwide angle lens. I got the lens together with a Kenko Pro1D 77mm thin protect filter and Hoya Pro1 77mm thin C. Polarizer (they ran out of Hoya UV filter so it's the next best one out there). I did notice some vignetting with using the c polarizer on top of protect filter but I guess they didn't thought about stacking filters on a UWA lens. Now to use it more this coming holiday season