Did one in NYC. It was so much fun. We solved one with a 25% completion rate and we had 7 minutes to spare. We thought we weren't going to make it, but then with like 12 minutes left things really started clicking.
I was a little not sober and wasn't helping at all. I couldn't keep up with the pace, so I just sat down with a puzzle nobody had solved. You had to go thru like 50 books to find a pattern. I looked at it for like 20 minutes. Everybody was so happy I got it, nobody cared I didn't do anything else.