• I’ve played the first chapter of single player, and the game seems to maintain all the wit, charm, and humor of the original but with some well…much more varied and interesting environments.
• The coop portion I’ve beaten, and it was A TON of fun, while the puzzles are technically more challenging you’ll generally find that when you have two people working simultaneously on a puzzle you actually figure things out faster, cause in one level you’ll have something figured out quickly while your partner is still perplexed, and in others it’s your partner figuring it out.
• At least this was my experience where it was basically my friend and I switching giving each other orders on what to do, cause one of us would figure it out.
• Absolutely recommend playing this coop, although it’s probably worth it to find someone who hasn’t gone through it yet as you’ll have a lot more fun solving the puzzles for the first time together.

• I’ve played the first chapter of single player, and the game seems to maintain all the wit, charm, and humor of the original but with some well…much more varied and interesting environments.
• The coop portion I’ve beaten, and it was A TON of fun, while the puzzles are technically more challenging you’ll generally find that when you have two people working simultaneously on a puzzle you actually figure things out faster, cause in one level you’ll have something figured out quickly while your partner is still perplexed, and in others it’s your partner figuring it out.
• At least this was my experience where it was basically my friend and I switching giving each other orders on what to do, cause one of us would figure it out.
• Absolutely recommend playing this coop, although it’s probably worth it to find someone who hasn’t gone through it yet as you’ll have a lot more fun solving the puzzles for the first time together.

The game is great fun, but the complete lack of replayability sucks hard. 

True, but the puzzles in Portal 2 weren't that hard to begin with. SP had some challenges (two of the latest rooms had me almost yelling at the screen) and some of the latter maps in the MP is kind of hard as well. But mostly those "oh god... lol? wtf?" moments from Portal are gone, and I blame Valves playtesting. It's nice of them to think of the crowd, but man, this needs to stop - they can't take everything away just because someone looks at another wall for too long. Close to the end they even made a task foolproof to ensure people getting it right - no matter what portal you place, it will be the right one.