P90's not noob...it's a good close-range SMG
Martyrdom can be a n00b perk, but personally I use it to set ambushes, get killed, have a few guys around my body, and boom, 2-3 extra kills
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It gives me a nice warm feeling inside
Claymores and stun 'nades ROCK. If used right. Too many n00bs fire them off at anything.
Last stand is a great perk, I've been in situations where the guy kills me, I get out my pistol, he's turned around, I headshot, get 'WTF????? HAXOR!' in the chat.