We were near the front. A few times in the first few minutes people entered from off stage to "surprise" the narrator. They shouted very loudly (as actors need to do to reach the audience in the back) and scared my 4 year old so badly that we had to leave the theater and didn't come back. (There were a number of other young kids in the lobby who experienced the same fate)
We had grandparents with us who offered to stay in the lobby while we watched the rest of the show. Curious and sometimes creative alterations to standard fairy tales, but a lot of the humor was a bit negative and mean spirited. For kids who don't yet make a distinction between appropriate behavior in the "real" world vs the "theater" world, I think this would require a lot of explaining. (Why was so and so shouting so much at ...? Why did so and so play a mean trick on ...? etc)
We've been to a number of performance over the past year. Each has been magical in its own way (ZooZoo and Return of Cats, a few of the Tears of Joy puppet theater, Curious Garden Theater). We had high hopes for Stinky Cheese Man, but even if our 4 year old hadn't been so scared that he had to leave 5 minutes into the show, I think we would have been disappointed. In my opinion, the show lacked the imagination and the sensitive to be successful for an audience under 5 or 6.