All I can say is, the people who obsess so much over Halo on Xbox (as opposed to PC) obviously haven't fully experienced the true joy of using a mouse and keyboard. Once you're used to the mouse and keyboard, there's no going back. The controller is an inferior system to use for FPS games, there's no way it can possibly compete.

EDIT: Agreed, Assertn, M&L Superstars was fantastic! Might play through it again actually.