We took the UnDISCOVERed Future World tour last month, which entitled us to come back and use the Italy VIP area for Illuminations that night. It really is worth it. You get an excellent view of the show, and they really limit the number of people who come in. We got there around 8:15 and the CM told us, "go ahead and look around in the world showcase for another half hour. There's really no reason to come in this early." When we came back, there was still plenty of room at the rail.
We didn't know about the VIP viewing area until the end of the tour when they told us. We actually had our Fantasmic dining package that night. I couldn't cancel that because of the 48 hour cancellation policy, so we went over the MGM for dinner, but then decided to go back to Epcot for Illuminations. We'd already done Fantasmic earlier in the week, and decided to use the Illuminations VIP area instead. (We made a honeymoon couple we saw in the park very happy with the Fantasmic passes.)