Mack also makes them. They've built Journey to Atlantis at Sea World Florida and Poseidon at Europa Park. JTA, which I believe was the first ever liquid coaster, is mostly flume with a bit of coaster track towards the end. Poseidon, which opened last year, has much more coaster track.
Premier is building their second liquid coaster, Vonkaputous, at Linnanmaki in Finland. And there are plans for a second Journey to Atlantis, at the Sea World in San Diego. I would assume Mack will be building that one.
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I know a little German. He's sitting right over there.