This game is now free to play. Which means that it doesn't cost money. None. Basically this means that the price v.s. quality equation is infinite, so there's no reason not to play it. I can see some reasons why you won't play it:
a. you suck at first person shooters (solution: read the article I linked Propain to some posts earlier)
b. your computer can't run it (solution: use
this config)