I agree with all the folks who say that this is their favorite crop-body wide lens. Occasionally, I wish I had a little more light gathering, but otherwise, it's a great lens that tends to take very crisp shots.
All images below were shot on an XTi.
1/250 sec, f/10, ISO 800, 10mm
1.6 sec, f/3.5, ISO 100, 10mm
1/40 sec, f/4.0, ISO 400, 13mm
1/30 sec, f/4.0, ISO 100, 13mm
1/6 sec, f/3.5, ISO 1600, 10mm
1/50 sec, f/4.5, ISO 1600, 10mm
1/20 sec, f/3.5, ISO 1600, 11mm
15.0 sec, f/3.5, ISO 400, 10mm
1/200 sec, f/11, ISO 100, 21mm