When I first bought my Xbox, it was about 6 months after Chaos Theory came out. I had played it at my friends and on my old PS2.
I didn't like the PS2 version as it sucked. So, when I bought my Xbox, I bought Chaos Theory!
I had fun playing the 1P mode, but It was lacking... The "Rag-Doll" engine makes the game a heck of a lot more fun to kill with, but It didn't really have that edge, it was same old same old. My favorite missions were bath house and cargo ship.
Co-Op mode is a heck of alot better, because you can use an array of new techniques, that, unfotunatly, Sam couldn't pull off. And, the fact that it plays a part in the 1P story mode makes it more realistic. (To me anyways)
best feature of splinter cell chaos theory is Versus Mode. This mode I would play every day until I discovered halo and halo 2. I still play it every once and a while. It is incredible the way you can play, the glitches you can do, and the strategies you can use. There are 3 modes, Story, Disc Hunt, and Deathmatch (My favorite). And, a new feature, is that the host can change the weapons that everyone has, unlike Pandora Tomorrow. The Only reason I give this Game an A+ is because of VS. Mode.
Ok, so, overall, this game is AWESOME! I loved it! I recommend it for those who like Shooting Games, and even for those that don't!