Not mediocre by ANY standards
If anyone, even the critics, ever slandered this game its simply because they didn't put up with it long enough to learn how to survive in it. There are no tricks either, its not a cheap game.
Once you get used to the controls and learn how to dodge fire and retaliate it stops becoming frustrating, and that for me was only 1 hour after starting to play, so while im writting this i have to wonder how much the gamespot critic really played, or wheter they like this genre at all.
Once you learn to play the game it doesnt looses its charm either, the game becomes fun and its pretty easy to play, but all the same remains a challenge since the maps and the AI are well made. Plus the difficulties arent impossible so both the quality replay-ability of this game are quite high.
I never give a 10 to a game unless it has absolutely no flaws, that is not even 1. So if you are reading this i guess you can imagine im not really making that big a deal of this game, its just that this game IS that big a deal.
If you dont believe me then buy it like i did.
EDIT: back when i was a teenager I even got blisters playing it up to 4 AM in the morning a monday when i had highschool tests the next day, if i being the bookworm nerd i was at that age thought it was a good game enough to neglect my studies then what quality could this game be i wonder (sarcasm) xD