I totally know where you are coming from after buying it for the PS3, not only does that annoy me but martyrdom perk does as well, its just unrealistic - put a whole clip (30 bullets) into them just for them to either 1) Drop a live grenade or 2) Fall on the floor and pull out a pistolMade an error earlier. You can enter prestige mode 10 times. Multiply 55 by 10, and that's the amount of rank levels there are.
And I've actually got a complaint about the game now! I hate the perks. They're annoying as hell. I'm tired of losing kills due to Last Stand. I down the enemy just to have a teammate come up and finish him off.