Free, but that's one of the only attractive features.
Environment graphics are player models are pretty nice, but player movement and overall game mechanics are reminscient of something you'd see in a game from the 1990's. Aiming is also cumbersome and sloppy. Add-on's might be cool if you can get past the poor gameplay. Finding a game is pretty easy, and it runs decently -- even at high quality -- on my factory 2-year old Gateway.
Even if the game was decent, I'd probably get annoyed with people much worse than me being able to rape my toon simply because he spent his allowance on a Carl Gustav.
Took me longer to download it -- even with a 30MBPS FiOS connection -- then it did to play it and promptly remove it. Shell out the $20 and buy Counterstrike, Battlefield Bad Company 2 -- hell, even Team Fortress Classic would be a better choice.