I like source mainly because of how more interactive the enviorment is. I mean you shot a bottle andit moves, shoot a PC and it falls apart, shoot a chair and it moves. Also how the players fall (its natural) when you shot a guy he doesn't fly though a wall. And the glass is great fun

I love running though glass.
Also I like the p90 on CS source, killed 6 in about 10 seconds with it today on a mad rush into a heavly defended area (pure luck).
Don't see how i ever played CS:CZ
whats that mointor that mointors your FPS and all.