They have a rock shield, so they're good on dry rocks, not so great on wet rocks.
It wasn't the slipping, but the sole felt slightly inadequate, especially on small, railroad-ballast sized rocks. Jury is out. Certainly terrific on grass.
Wow, I've found sole really excellent on all dry rocks. But I guess that's compared to some really thin stuff, like my trailroc 150s and various street racing flats.
It's because you are dancing, light-footed across the rocks half again as fast as I was/am.