We had a fantastic time on this tour. There were 4 of us that did the snorkeling in the cage. I was a little nervous to do it, but it was so easy and not scary at all. The staff was very helpful when getting in/out of the cage. There were some children in another group that they handled very well and made them feel comfortable.
We were staying in Waikiki, and instead of paying the 100 per person for the shuttle, we just rented a car for the day for around $50 USD. The drive was easy and we were able to stop at a number of beaches on the way back to make a full day of it.
The only problem was that 2 of us got seasick. So definitely take some Dramamine if you are prone to motion sickness. I would also recommend bringing water and snacks.
Overall, we absolutely loved this experience and would definitely do it again, it was well worth the price!