We did it this August. Our kids were 7,5 & 5. They had a blast, and, except for the heat, we all had a good time acting a little Goofy and a little Dopey. Our tour had 4 families, or about 15-20 people total. We had about 1/2 hour at the end of our tour with 2 characters, and then we went with them to see Philharmagic. I don't want to spoil any surprises, so if you want more details, PM me and I'll PM you back.
At $25/person, it was a little steep, but as a one-time, something out-of-the-ordinary activity, we thought it was worth it. I think it will depend on how old your kids are and how willing everyone in your family is to let loose and act silly. (We had no problem with this, after all, we're never going to see any of those people again!)
Hope this helps.
Mike