Well the game is old, witch means you can max out the graphics fairly easily. And they do look awfully good. Especially in the latest 1.4 version where you have HDR and the ability to put on various visual filters, for example there is a mode to make everything look cold, there is the enhanced color mode, the tropical paradise mode, and my personal favorite, the cartoon mode. Yes you can play this game as a cartoon.
The game play I think is very fun. The guns all feel right, and there are many guns, and the levels are very well designed. Basely, you have to go complete the objective on a jungle level filled with angry mercenaries. It is fun. There are cars, forts, bunkers, boats, and multiple paths to every objective. It is as I have heard Crysis described: a "Sandbox Shooter". Oh and the violence is most excellent.
The story sucks, in a good way. It is like one of those bad Sci-Fi Channel movies. But it is genuinely enjoyable like that. This game is funny at times as well. The mercenary barracks are all full of "Red Neck Magazine" and "Guns Magazine", or even "PlayMerc". The enemies say the most ridiculous phrases, and every cut scene is cheesy.
My few complaints about this game are:
-No real Iron Sights, just a Fallout 3 style zoom thing.
-The later levels are much more railed and not as free roaming.
-The friendly AI sucks. I had to restart a level a few time to get my lady friend to follow me correctly.
But this game is so enjoyable that I can easily overlook these problems.
Before you play this game remember to set the body fade away to 999 seconds. Makes the game more fun.