I loved that game. I borrowed it off my cousin back when it first came out and it's the best shooter I've ever played. One of the best things in it, and something that missing in a lot of games now a days is how hard it was. When ever you finished a level you felt like you'd achieved something. Possible spoiler
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The ghillie suit snipering level was the best in the entire game, I even lost sight of my mate a few times when I first played it


And there is plenty of replay value, especially if you start on a low level and try a harder level on each play through. The ending however is very abrupt and I didn't realise that I had finished the game until the credits rolled.

I think this review explains the game rather well. WARNING: the review has very bad language.