I'm thinking that some of you guys don't understand how fast an attack happens. If you got off one or two shots, you'd be lucky. So having 6 or 20 isn't going to make a big difference, but how much stopping power that one round has when it hits its target, will. I'd rather have one 300+ grain bullet out of my .44 mag than one 9mm round, reach its target. I want bone crunching kinetic energy, to impact with that massive predator.
Truth be told, you're better off with spray followed up by a lead chaser if necessary.