Just got it yesterday. Great game, would have been awesome if there would be co-operative mode on live-play.
That game indeed rocks, especially if you are a paintball enthusiast like myself.
The career mode isn't too bad. The AI is actually pretty good.
In the later tournaments, you need to pick and choose your teammates wisely. Personally, I like to go with two or three front players, two mid, and one or two backs.