I havent played this game in a few years but it was by far the best FPS for PS2 in my opinion. I like the destructable environments and wide range of weapons. The story line is kind of cliche but other than that the gameplay and general feel was pretty original.
I don't know why this game didn't take off, it was a fun original FPS. FPS games have a tough job, keep you interested in basically what is doing the same thing over and over again, killing. This game does a good job. REVOLUTION!