I'm using this on a Canon EOS 50D. I only have a few hundred shots on it so far, but the image quality seems very good, maybe even better than the Canon 28-135. Very little chromatic aberration or vignetting, and the images are nicely sharp. Of course, I wish that it had image stabilization, but for this price and IQ, something had to be sacrificed. In any event, IS isn't as vital for a short focal length as it is for my telephotos.Oddly, the cap that fits over the back of the lens when the lens isn't on the camera seems to have a funny fit, so it's more work to use than the typical Canon cap. But I consider that to be more of an oddity than a real issue.