I did the tour in May with my three kids, 7, 5 and 15. We were the only people in the group. I would rate it just okay. The girl who did our tour was nice, but the whole storyline felt very forced. My kids had a good time, but I wouldn't say it was worth the money. A lot of times it felt like we were just walking all over the place. For some reason we didn't even go on the first attraction to find the answer to our first clue. The ride was running, so I don't know what happened there. My kids love scavenger hunts and puzzles, so I just can't put my finger on exactly why the tour wasn't that great for us, except that the tour guide just wasn't very engaging.
I believe the tour used to have a lot of character interaction, which would be great. But since they redid it last year, that element is gone.
I would say you'd be better off making up your own little scavenger hunt type thing for the kids. Get a book on hidden Mickeys or something along those lines.
I know others have said good things about it, but it also seemed like a lot of those reviews came from people who had done it before the change.