I've now got about 1,500 miles on the tires with no problems. I babied them for the first couple hundred miles due to my experience with the previous set (and some GP4000SIIs) getting damaged, avoiding a couple of several roads which have some sharp gravel and which are prone to road debris. I don't worry about it now. I've also ridden a few miles of dirt. So far so good, which probably means I'll have an issue tomorrow.
-Matt