The stock pucks are made of brake pads material with small bits of cloth like material mixed into the pucks. They were brittle when I broke one in half. Carbonium is the same material we use on our kart's clutches. The carbonium material is harder and will last longer. A couple of us have the new pucks in our clutches and are going on a 40+ mile test ride today.
I'm really surprised you guys haven't shredded your stock pucks yet.
Its probably b/c we ride hard 80% of the time.