We just did this for the first time two weeks ago. (thanks to a Dis-er who gave us her cancellation!--yay sburke!)
We loved it. We would love to do it again, but we always make last minute trips, so it's hard to catch that 90 day window, darnit!
I agree that there are better views from other places in Epcot though; we did expect the view would be better--but we loved it for the convenience, the no-crowd thing, no staking out a spot, no fighting for space--etc. We only had the three of us on the boat and liked that--we could all lay on the seats up front. I wouldn't care to be in the back of the boat, or on a boat with the maximum people unless they were all family or close friends. We had Captain Ron and would request him again (does that work?) he was awesome! I can't wait to do this again, and will try to do this every trip. We are really water people though, we love boats.
One thing I would change--I would like to be on the boat longer. I wonder if it is possible to get the boat for two hours?