We were just in Hawaii in June and went on the Napali/ Nihue snorkel tour. Our trip was an 11 out of 10. Seas were releatively calm that day 2 -4 ft. Captain was very knowledgable. Slowed down to go with the dolphins. Snorkeling part was excellent visability to about 80 ft, saw large variety of fish, an octopus, and a 3 ft reef shark, turtles. I also enjoyed watching the captian snorkel dive ( he would go down about 30 ft). We saw rough toothed dolphins, spinner dolphins and bottle nose dolphins, and flying fish. To top the day off as we were heading back to port (already at least 30 minutes over our 7 hour tour time). The boat came to a sudden stop, and the crew started running around getting snorkel gear ( I was sitting in the cabin at this time and thought someone fell overboard), but no it was the last of our marine sightings for the day. A 25 - 30 foot whale shark, the captain allowed anyone that had gear to go in for a visit -- I only wish I would have known that a whale shark was a filter feeder earlier. The people that went in said that it was an awesome sight. I doubt that if we went again it would be the same, but there were several people that had been out with this group more than once. You will get wet, you will get a lot of sun, but it was the trip of a lifetime. We used the entertainment coupon.
On a sideline we went with Captain Andy's last year. I enjoyed the trip, the group as a whole was more a "party group", but the captain, snorkeling, and marine life sightings did not hold a candle to Holoholo (Before Holoholo I would have given Captain Andy's a 8 / 10 (boat trip 10 /10, snorkeling wasn't worth the effort of getting the gear on)