Do CAM phasers go out often

No, it isn't a common problem. They are strong engines. The one concern I have with these engines is this. The spark plug threads are very shallow. There have been reports of plugs actually shooting out of the heads. I have never experienced that, but I have experienced the threads coming out with the old spark plugs. If that doesn't happen, they usually break with only the threads stuck in the head. They have developed tools to remove them. Before, we had to remove the head and send them to a machine shop to have them heli coiled and repaired. NOT A FUN OR CHEAP JOB! Back to your original question, it isn't common, but it does happen.