Absolutely Astounding
Hah love the CS Zombie Mod BGM. That and the headcrabs. Valve is win. And so are you.
It gets kind of boring after you get to the expensive guns, as all you have to do is spray everywhere. Still very fun though.
Although I'm not sure how you can have so many corpses, shells, and pools of blood laying around without lagging the crap out of the game.