The main reason I picked up this game was nostalgia, I played the first mission over and over on a Demo CD for PS2. Once I got past the first mission, I started to realize that the game hasn't aged well. It's clunky, the aim is not responsive, the menu is not intuitive I was starting to rage on this game. But then I sort of began to push trough and was starting to feel real acomplisment when a mission ended. You have to consider that this is a pioneer of the genre, it lacks polish, but it has fun objectives and I really love switiching between characters. If you can find a buddy to play in co-op it´s even better! I hate/love the fact that you can only save 2 times during a mission, it makes things much more challenging and puts you on edge, specially if you're trying to go without sounding the alarm. Even the silly story is engaging, and with a great payoff. I ended the game with a nice feeling of accomplishement, I recommend it to someone who likes tactical shooters and doesn't mind a little masochism. ( I also had a bug that makes a character get stuck in the air, I finished the game without solving the problem, just with lots of patience and stubbornness, but don't do it like me, visit the forum, there are some solutions for this bug.)
I mostly play games for the adventure and the story. This one tells you so little that you treasure everything you find. The mechanics are odd but i like them, gives you more time to develop a strategy instead of button mashing. Hooray for an indie game that isn't a side scroller! ;)