We went on the Keys to the Kingdom tour in June. While the information about the Magic Kingdom was interesting, our guide was overly fascinated with the Haunted Mansion. We went on the ride twice, the first time without any inside information and the second after she provided us with some insights. The tunnels, frankly were disappointing. You're not allowed in the character area. We saw some offices, a medical team driving their cart to position themselves for their shift, some pictures of the development of the Magic Kingdom and EPCOT. We also learned how garbage is moved via vacuum tubes.
We're glad we took the tour, but I frankly doubt we'd do the 7 hour tour of all 4 parks.