Rastoff, that's not quite correct - I think it's 230 grain FMJ hardball...
This is correct if you're referring to the round that was accepted along with the gun back in 1911. However, the 200 grain round has been around just as long. Probably not as popular, but still effective.
...but you don't need to be sending that kind of ammo at your perpetrating opponent who has who knows what behind him in terms of innocent bystanders. Or has a drywall behind him and a baby's room is next. You want expanding ammunition.
If we ignore rule 4, then you might be correct. However, concern of over penetration is not high on my list. I've done some penetration testing with the hardball stuff and it's very unlikely that it will go through a bad guy, through a wall and into someone else.
I've also seen a lot of penetration testing with JHP rounds. In ballistics gel and liquids they have good expansion properties. Every other material, not so much. I even know of one guy who shot himself through his right thigh and into his left calf with a .357Mag JHP and it never expanded (lucky for him).
I'm not minimizing anything here. I have as much concern for my fellow man as anyone. It's just unlikely that I, or anyone else, will be firing into a crowd. Again, rule 4; be aware of your target and what's in line with it.
The most important consideration of a defensive firearm is functional reliability. If it don't work, it's useless. I've tested my 1911 with thousands of hardball rounds (both 200 and 230). I have fired a few JHP rounds through it, and they worked, but haven't fully vetted the gun with them. So, I see no reason to change.
Just out of curiosity, does anyone here have an article, or case law, where an innocent was injured/killed by a round that passed through the bad guy?