I know I am about to offend some of you, however if you live in a residential neighborhood a 223 is not ideal for home defence. You are firing a round that can easily penetrate your drywall and siding and then your neighbors and kill someone next door or down the street. Unless you live in a log or all brick home, a hi velocity rifle round in a neighborhood is a safety hazard. And you need to make dang sure you don't put a round through a window or door.
I agree... But as we all know, common sense is not so common anymore.
Everybody wants a 5.56 AR pistol for home defense. By all means, don't stop there, the 308 is a awesome man stopper as well.