We took the 8:00am option. This was a huge mistake. First, our pickup location was changed and we had to Uber there (vs. walking across the street). Second, once we arrived at Hanauma Bay, we had to wait 3 hours before we were able to actually get in - leaving us about 1.5 hours in the water. The bay seems unhealthy and we saw only a few fish - which was extremely disappointing since it was 4 hours from when we were picked up to when we got in the water.
You can pay for prescription masks (which is ridiculous since other rental companies do not charge for this), but you need to tell them (they will not ask). You can rent chairs and other stuff too (which you probably don’t need). Be prepared for the company to contact you multiple times - which is annoying when you are on vacation and potentially on another tour.
Maybe if you take the 6:00am tour, you won’t have to wait so long, but do not take the later tour. To be honest, I’d just buy (or rent) snorkel equipment and take an early 6:00am Uber there - then you could stay as long as you want. Make sure to pack a cooler with sandwiches/food and waters.