Is the extra 100mm focal length compared with the 300mm f/4L IS worth getting this similarly priced lens? Not really—you’d do better getting a 1.4X tele-extender for the 300mm. Lacking IS, this one has outlived its usefulness.
Almost a must for serious Canon shooters. Sharp, fast, and very well built with quick, accurate and quiet autofocus. Well-sealed against dust and moisture. Very Visible barrel distortion at 70mm (1.28%).
Excellent introduction to pro-grade glass, and much lighter and less expensive than the brighter Canon f/2.8. You still get L–series construction, optics, and handling, however. Tripod collar (A-2) is a separate purchase ($150, street).
For Canon soccer moms and vacationistas wanting image stabilization. It’s got light weight, satisfying magnification (1:2.85), and the right price. Not the most rugged build with a plastic lensmount and scaleless barrel, but quite sharp.