Hello all, I am a new member here and wish I would have come here sooner. There is always great debate over 9mm and 45 ACP. Truth is, new advances in 9mm ammunition have closed the gap between the two considerably, to the point where the 9mm may be the better option for most. Here is a link I ran across that does a pretty good job explaining the different, and preferred, defense ammunition. This article covers everything from 22LR on up. It's worth the read.