OK. You've touched on something that I know my response is going to upset a lot of people here, but here goes-Timmy - no single bullet from either a handgun or rifle is guaranteed to stop an assailant. Police have put more that twenty bullets into an individual before stopping him. There was one marine sniper, Carlos Hathcock, who shot three big bore 30 caliber bullets into individual before he dropped. When faced with multiple assailants, it stands to reason that more than ten rounds are desired. Someone else linked to a home invasion where the homeowner wished she had more than ten rounds to repel the three assailants.
Just because the police have access to a weapon doesn't mean a private citizen should. Police have a different set of responsibilities than private citizens do. Any argument you make to me giving police as examples aren't going to fly, because their use of weapons have nothing to do with private ownership of said weapons.