With the release of user created level of Portal 2, I thought I should go back and play the DLC that was released for Portal 2 a ways back. It turns out that the DLC is only or co-op mode, which has it's ups and downs, that is tied to the quality of your team mate . If you don't choose some one from your friend's list, you will be randomly joined with another member, and you never know what you are going to get. I got a mix of every thing, a couple of kids who sounded really young and didn't really seem to understand the concept of the game, a few people who wanted to give up after they couldn't find the solution right away, as well as one guy who just rushed through the level, without give me time to solve it on my own. But there were two or three (all that were needed to get through the DLC) people who were spectacular and cooperative. It's those people who make the co-op levels on par with, or perhaps surpassing, the single player game.

As for the levels, all I ever asked for was new levels for Portal 2 and that is what this DLC gives you. The new mechanics added to Portal 2 (that didn't exist in Portal 1) were unexpected surprise for me. This DLC doesn't add any additional mechanics, but you would be better off playing the prior levels of Portal 2 co-op before trying the DLC. For free (for owners of Portal 2), that make a great deal, as the levels give more of what you expect from Valve and Portal (and GlaDos)

I had no idea how to access the DLC before I played the game, since just looking at the game menu gave me no clue where to begin, but once I was in the right game mode, it was fairly easy to figure out what had to be done to access it.