I like the box section rims just because they look better on my vintage commuter. I decided to give the CR-18s a try and have found them to be pretty darn rugged. I put ~4000 miles on one set that was laced to a SA S2 on the back and a Shimano Dynohub in the front. 36H, 4x, and straight gauge 2mm DT spokes. Although my commute is 95% paved streets, there are some rough sections. Also there is my tendency to speed up over speed bumps. The CR-18s took it all in stride. My personal opinion is that it is less about the rim and more about how the wheel was built as well as keeping good tire pressures.

I loved the S2 hub, but it took about 500 miles to feel competent with gear selection.

-G