I took this tour about 6 years ago, so I am sure alot has changed since then , but thought it was a great tour. Sure, its all day but you are not walking the entire time. While some contents overlap with other tours, such as a tour of the utilidors, on this tour you get to see(atleast on ours) areas not available on other tours such as the huge holiday warehouse(mind boggling the amount of xmas decorations), laundry facilities(it actually is interesting), underneath the american adventure pavillion, the castmember building at epcot( a glimpse of life off stage), the large central repair and maintenance facility where rides and attractions are worked on(fascinating!), etc. Back then, for some unknown reason, the tour did not include a stop at Animal Kingdom. We also had a filling 3 course lunch at Mama Melrose at DHS. We had an excellent CM which really makes for a great day, alot of interesting info and trivia.
Now thats its been awhile, I am looking forward to taking it again! I hope you will find it as interseting as I did. You made a good choice!