DefiantDad;
The problem with single incidents, is they are just anecdotal evidence. There's not enough of a basis to form any seriously meaningful comparisons. Not that any comparisons are really necessary, 223/5.56 has proven to be quite lethal enough to keep using it in our military for a couple of generations.
Would the guy have expired from 40 cal rounds? Probably. I mean, the guy was shot what, 17 times before he went down and they STILL had to wrestle him in to submission to get him cuffed? The fact he wasn't on drugs or alcohol and took that amount of punishment is just mind boggling. If ANYTHING came out of that report that is frightening (other than the pictures), it's what the human body and mind can withstand and still fight.
(Which lends some reinforcement to concealed carry / personal defense. Unless I get hit with a central nervous system done-and-done shot, I guarantee I'll have enough life left in me to make a decent effort at ending my assailants..)
As far as 223? All you need to do is remember, criminals can buy body armor too, and you can't pick who invades your home, or what they're wearing. Handgun rounds MIGHT not cut it. Sure the odds are slim. But if they happen, wouldn't you rather have a little too much gun, than to come up short?
Always have the most gun you can have, if you're preparing for a gunfight. Home defense is no exception.
I mean, I wear WAY too much hot gear - leathers, helmet, boots, etc - when I ride motorcycles. But... I'm dressing for the crash. Not the ride.