I don't know about having the choice of shells, or the reliability advantage of a double, but I know several bolt action shooters who can work their actions unbelievably fast. There is nothing like using what you know best in tight situations. I am a guy who used only double shotguns for years until finally got a pump last year. It is hopeless for me. So I would hate to have a PH protecting me who grew up shooting affordable bolts, but now had reached the point where he could own a double. If you tell me that the PH is a professional and will be cool when a problem arises, well sounds good, but how much experience does a typical PH really have with rescuing a client in trouble? How many times in a year of working does a PH find he actually has to fire to protect a client?