The best fps action/rpg game out there!
Even in the beginning you get totally hooked by the gameplay, because of great graphics funny and remember able characters, solid core gameplay, and great RPG elements.
The gameplay is very solid with funny and sometimes optional quest however it is a very linear game (to some parts) but that's not really a problem however because you get to play around as much as you want and meet new enemies and scavenge as much as you want.
The voice acting is also very good and the loot system is very balanced.
Even though this is mostly a Co-op game its still very good single player but when you played it for about 30 hours single (which i did because my internet didn't work for a while) it gets somewhat tiring.
The whole RPG element is very well embeded into the gameplay and its not something that you really think about like MUST LEVEL UP! or something... Every time you level up you gain 1 skill point to put in various skills.
The great part about the whole skill assigning is that you have 3 different paths to go with each character, but dont get me wrong here you can put them scattered throughout the 3 different "paths" and not just being able to choose one of them.
Another great part about it is that if you do not fell completely satisfied or you just want to try something else you can go to a respawn station which are scattered all over and reset all your skill points for a very small sum of money.
As a mentioned earlier the characters overall is really well made with good acting, design and actions both AI controlled and quest characters.
There is a background story to the whole game as well which has you go look for the legendary "Vault" that you heard about as a kid.
The missions are both based on story work and just random missions but the story is kind of weak....
But overall if you're looking for more action then Fallout 3/new Vegas but still want an RPG try Borderlands out :D