Borderlands is probably one of the best games that I have played in a while. The only cons to the game are that it uses gamespy for online (it doesn't lag when actually playing the game online, but the lobby is slow as shit and takes forever to refresh and show the servers), there's no option to change crouching from toggling to holding the crouch button, and some minor graphical errors that aren't really noticeable. Definitely worth fifty dollars and so much fun online with friends. It's sort of a straight port from the console version but it works and it's a lot like CoD4 for PC, with the shooting and control scheme (Which is customizable except for being able to toggle or hold the aiming button, but I like having it as having to hold the aim button to aim instead of toggling).
9.7/10
Side Note: Gamespy fucking sucks, I played Tom Clancy's Rainbow something back a long time ago with gamespy and it still sucked for its time.