The arguement about the difference in ammo is almost moot. Lets put it this way.
If someone breaks into your home, statistically speaking the chances of you EVEN HITTING that person are slim to none. You guys that sit there and waste your time playing with ammo changes read too many stories on the Internet.
One of the deadliest bullets in Chicago is the .22. Why is that?
Do yourself a favor. Buy the CHEAPEST shit out there and load up. Done deal.