I got the ps3 eye with facetrack noir, uses about 7% cpu for me, not sure about ram, it does occasionly glitch and you have to wait for it to auto restart itself, I'm far to lazy to do the free track, though I might get a trackir at some stage.Between clod and fsx I need all the cpu I can get.
heres what you can expect with facetracknoir, ps3eye and an i7