I had done all of the the research before arriving on the island and had sold about a dozen people on the idea. Based on both their price ($30 including unlimited drinks) and excellent reviews, I had booked all of us aboard the Na Hoku II. On the given day, I had taken "it's only a passing cloud" as my infallible mantra. I may have done an anti-rain dance. It did no good. In the end, we were all left sodden and minus one dazzling sunset (but not exactly thirsty, luckily, you can still get those mai tai's on land).