IT WAS AMAZING!!!
I did this tour in July with my parents and 16 year old brother. I think it's an undiscovered gem so we were the only four in the tour, which meant it was like our own private tour.
It focuses on Future World and you spend time in each of the buildings. We got to go into VIP lounges, we were backed door into Soarin' to show us how VIPs board the attractions, we learned a lot and our guide was absolutely wonderful. At the end we were told that we would have VIP seats for Illumintations that night - which was a great treat.
Our tour guide mentioned that each guide does the tour a little differently, so you will not be guaranteed to have the same benefits we got, but you'll probably still get something.
The next day we went on the Keys of the Kingdom tour. I thought our guide was bland, the group was so big that it felt unpersonalized, and all around I was really disappointed - but I think it's because the Epcot tour was just so incredible the MK one couldn't live up to it.
I hope you love it!