Borderlands is an example of great a game can be even if it uses cell shading.
I now see why its still an expensive game after 3 years.
If you're going to play this game, do not let the cell shading fool you, this is far from what a typical cellshaded game offers you ... it offers much more.
This game is one of the best example of a shooter mixed in with what I think is the best class and experience builder to ever make it into a game.
When I play this game I have lots of fun, the weapons are fun to use which range from pistols to shotguns and machine guns to sniper rifles, and there are plenty of them.
The 4 classes you can choose to play as are all varied enough to warrant multiple playthroughs.
The graphics are outstanding, the game manages to keep a consistent frame rate and there are not that many bugs or glitches in this game which I think is really good.
The controls are very easy to master. It only took me a few seconds to master the controls, but be warned if you've been playing game like Black Ops or Crysis 2 a bit too much the control scheme will seem somewhat wried (PS3 version)
The main shine this game has is the 4 player Co-Op, you can all play through the main game together, I also believe there is a death match mode which is triggered by attacking another player on Co-Op.
I highly recommend you get borderlands, it is well worth the money.