Stats will be messed with your plugin.
You're not dealing with deadly bullets when armour still left. So you may die having enough armour for living.
I didn't use pre-damage, cuz it wold be crazy if you had to hit a player with awp twice, so I made armor-format check after damage.
By now i saw the exception. But AWP is just a one weapon. Well, then assume situation when you have only 1HP & 50 AP. Pistol bullet hits a player into chest. You're dead intstead of being alive & that is not real again.