Smoking Prime Rib used to scare me because it was a spendy piece of meat.  130 F is the perfect temperature for medium rare internal temperature, smoker set to 325 F.  Wireless meat thermometer has been a game changer reducing my chances for over cooking a nice piece of meat!  

Found another use for cake pans - they make great prime ribs, too!  I didn't trust the disposable pans to handle the weight of the prime rib when carrying it in the house.