Review on Canon EF 20-35mm f/3.5-4.5 USM Ultra Wide Angle Zoom Lens - Optimized for Canon SLR Cameras by Jose Haskin

This lens is good for those who want a good wide-angle lens but don't have the budget for an EF 17-40 f/4L. To beat the quality of this lens you have to spend almost twice as much. I used 20-35 on my Rebel XT which is 32mm x 56mm. It's not as wide as the EF-S 18-55 that came with the camera, but the quality is much better. The ring-shaped USM focuses quickly and silently. Overall excellent value for money. If you can afford it I would go for the 17-40 f/4L which gives you a bit more range. If not, then this is a worthy alternative. Another option to consider is the EF 20mm f/2.8. It's slightly faster but costs about $100 more.