I do break with an ob break shaft. It has a samsara jump and break tip on. The break shaft is a little thicker than the ob1. As long as you keep the carbon fiber on your ob1 shaft, I wouldn't be afraid of using it for breaking, but you should consider a harder tip than the everest (as already mentioned here). My playing shaft is an ob1, and occasionally I break with it, but for serious matches I prefer the break shaft with the harder tip.
-Jon Birger