Because I'm a cheapass I did a lot of research before booking Holo Holo. Compared to the competition $129pp was the cheapest for a 5 Hour Snorkel tour, which includes breakfast, deli lunch, 1 snorkel swim, and beer/wine on the way back. Due to crazy waves up north, we couldn't hit up the Napali coast, but they managed a fun impromptu sail along the south and west coast. The snorkeling spot was decent, but snorkeling at Poipu Beach was better, and not to mention free. The staff was friendly and knowledgable.
There was nothing wrong with this trip, but 2 years ago in Maui I booked a 6.5 hour boat trip with Pacific Whale Foundation (http://pacificwhale.org). Their trip included breakfast, hot bbq lunch, TWO snorkel swims at Molokini and Lanai, and booze on the way back...for only $86pp, so I don't feel like I got my money's worth.
Maybe its unfair to judge Maui against Kauai...are the two islands economies that much different? Regardless, Holo Holo is probably the best choice for boating on Kauai.
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