I've had a set of these since March, and I've been really impressed. They're the wheels I use for every ride, and I've taken them on reasonably nasty southern AZ rocky stuff (well nasty for me), trying to keep up with my friends on *much* burlier bikes.
I had one issue where the piece of the axle that fits into the dropout on the rear wheel broke. It seemed to be a manufacturing defect or something, tho. I had not done anything in the recent past that could have caused that, and apparently it's not really where the axle should fail anyway.
Anyhow, AC's customer service was excellent. They sent a replacement part to my bike shop next day air no questions asked, and I was back on the bike the next day!
Great stuff.