User blog comment:Cinder23/What is the best perk set up?/@comment-1079585-20100421120519

Marathon, Scavenger, or Bling (if you actually use two good attachments)

Cold-Blooded, Stopping Power, or Lightweight (only useful if you have Marathon and and an SMG/Sniper/AR)

Commando, Steady Aim, or Ninja (only in slower paced modes or against really good players)