I would compare this $9.00 title to the original SiN. Same basic maps and physics. The game engine looks dated for the most past.
Game play: Good. Fun shooter. Fun weapons and lots of ammo. Very linear. Some maps on Earth are the same as on the other planet you visit.
Story: Contrived. Nothing what you would think it is. An exodus from the Earth doesn't even take place or is even eluded too much of the game. The story is the same as most shooters (have a friend most of the game that turns into the real bad guy).
Sound: Bad music (when it plays). Same dialogue during action throughout. If I heard "He is smart!" once I heard it a thousand times. English translation horrible. Almost laughable except you really don't understand what they are trying to say most of the time. Even the written parts are bad translation.
Graphics: Dated but it only $9.00. It never crashed once.
It works but if you are expecting Crysis or Half Life 2 forget this one.