No one's mentioned the Pirelli Scorpion Trails, so I will. They look pretty tame, but I've had a set on my bike for about 4k miles now and am enjoying them. I've had them on a some rocky dirt roads and wet pavement and they've worked well. Just rode them over Hunter Mountain (back way into Death Valley), and out to pavement past Tea Kettle Junction with no problems over lots of dirt, gravel, rocks and washboard. Then more dirt and gravel into Nevada to watch the eclipse
. Certainly not a mud tire, a little squirrely in the sand, excellent traction on the street and perfectly good for a lot of off-pavement riding. And they're wearing well, too.