Every child is different, but it can be dark, and it is load in points (like the shooting, or the thunder strikes). Add the fact you are sitting on bench seats with desk like tables (like a University lecture theatre), and you are sitting in long rows which make getting out a challenge, it is just not something I would have done with mine. add to the fact they are usually really tired (and may be moody) at the end of a long day.
I waited until my youngest was 4, and she loved it. And we went in for EMH in the morning, but spent the afternoon in the pool, followed by a nap so they were not too tired. Just my 2 cents.
we took my kid brother when he we 2, and although he liked it, by about the middle he had enough because he was tired, and it really interferred with our enjoyment, and the other families in our ranch.