I don't know how long this feeling lasts, and this may be just me, but pretty much every kill I've gotten in this game has been tremendously satisfying thus far.
If you don't have a dual core and a good graphic card I wouldn't advise it.
Recommended Specs:CPU: Quadcore @ 2.0 GHz
I can actually count my kills D: and sad part is I remember each one, which is bad for how good I normally do at FPS games.