I was a bit skeptical about this game when I first heard about it. I don't have a PS2 so I didn't see it until it came out on PC.
The open-ended gameplay is a definite bonus as it allows unlimited playability, but the missions are always the same so what's the need to redo the storyline?
I can see why this game is blasted by "Awareness" groups, it can be disturbing with the wanton violence and carnage possible. I was able to get up to a 5* alert after using the cheat for a tank, and it's amazing how hard the police and FBI pursue you.
Overall it's a good game, but I don't think I'll be replaying it.