I am thoroughly enjoying your lost attractions series. Maelstrom is the only one of these I was able to experience. On the trips when my family visited Epcot, we inevitably spent the majority of the day in Future World, racing over to the World Showcase to try to do everything (which wasn't a whole lot) before the park closed. I remember being amazed at Maelstrom and I considered it on par with Pirates of the Caribbean. Even though I knew we weren't going to fall backwards down a waterfall, it really felt as if we could go over any minute. Maelstrom was a valuable addition to the World Showcase, which is dominated by shops and movies, which aren't huge pulls. While I'm sure the coming Frozen ride will boost Epcot's attendance, Maelstrom was a great dark ride and I'll miss it on future trips.