I did it last year.
The success of your tour is truly dependent on how good is your guide. We had a full tour and they had two guides with us. One of them was perky and funny, one of them of kinda dull and not so fun. Guess which one I ended up with?
People actually were very rude and changed guides mid tour, which wasn’t the big deal, it was how it was handled and what was said that bothered me. Sure I’d like to have the funny guide but I won’t be rude to a Cast Member to achieve that.
The tour itself is VERY informative and you get to see some very cool parts of Backstage EPCOT, the Christmas department, which works all year round, you see decorations from all over the resort and even from the cruise lines, you learn how they assemble the Icon Christmas trees, you visit Wilderness Lodge and drink a special drink, eat some cookies and they end the tour with a special gift and some Christmas songs.