Unfortunately, we were unlucky on our visit 10/15/21 and didn't get to see any mantas. It was disappointing, of course (2 friends of mine who've done this rate it as a thrilling must-do!), and since it was the last night of our vacation we couldn't go back the next night to try again. However, the lady I spoke with on the phone when booking was fabulous, the staff member who got us set up in our wet suits was very friendly, and I do believe that our guide in the water tried his best to get us to some mantas. I would still recommend trying this if you're in the Kona area.