Disclaimer-I have only run this once, and with a weak party.
I love the concept - a creepy and mysterious carnival! Who doesn't have flashbacks of the county fair as a kid?
Trying to herd the cats of my group was a challenge - all they wanted to do was fight. A great adventure for RP though. I had a blast. And the magic item was fun - I had a bard in the group who used it well in later adventures "Oh God, not that again???"
And if you get the chance to play the related CCC, then this is an awesome lead in.
High for a RP group, low averae for a combat group.
[4 of 5 Stars!]