I've been twice with my nephew, when he was 2.5 and then 3.5, and he really likes MNSSHP. He loves the parade, and last year he really enjoyed trick or treating. I wasn't into the idea of ToTing, since so many people here say it's a waste of party time, but it was the first time he was really old to get into it, and he loved it, even though he's not even the biggest candy fan. I think both years he took a short nap in his stroller. So yeah, I'd recommend it for a 3 year old!