A gem

It's a small, handy, sharp zoom lens that comes very cheap in the used market. I owned it once and used on 1D Mark II N, 1D Mark III and 1D Mark IV but ultimately gave it away to a friend who was starting the full-frame kit and didn't have a standard zoom. Then, I decided to buy one again and got an unbelievable deal on a rare silver version. What's not to like?

From my experience mainly with the 1D Mark II N and 1D Mark IV, this lens is fairly sharp, especially stopped down some (but still very good in the center even wide open). The CA become noticeable towards the long end. The color is a little worse than the L lenses (duh). The USM drive is great although not quite as snappy as on the higher grade lenses (again, duh). The zoom ring action is not very smooth. But all in all, for $90 (or even $180 that I paid the first time), it's a gem. I wish Canon had updated it with IS like Nikon has done with their (very similar) model instead of / along with giving us the two much bulkier alternatives - the 24-70/4 L and the 24-105 STM.

Disclaimer: I never used this lens on an FF camera so I cannot comment on its performance in this regard.

Disclaimer 2: I give it 3.5 / 5 stars. 3.5 stars is not "rock bottom", it's actually on the better side of average. Since this is a budget zoom lens, one cannot realistically expect it to have higher ratings due to the obvious shortcomings that I've described above.