If you MUST visit Turtle Canyon, I’d happily recommend this tour.
However, my strong advice to anyone with an alternative (a car so you can travel elsewhere on the island) is to avoid all trips to Turtle Canyon. Our crew were perfectly nice (if frankly bossy) but arriving in a spot where approximately 100 people are already in the water in a space maybe 50 yards square does not make for a special trip. Frankly, it felt like visiting a dingy zoo twenty years ago. All the rest of the journey is padding but putting lipstick on a pig doesn’t change the pig.
Our friends drove to the North side, rented paddle boards, and paddled happily, and alone, with turtles. I know which I’d rather have done.
My guess is that that 50 yard square bit of sea generates about $10m of revenue a year, but if the government cared they’d limit visits to one boat at a time - better for everyone.
None of this is to say that this trip is worse than others to the same place. The cat was big and nice. Drinks were available for free. Crew, when not issuing orders, were good and friendly.