they were excellent - we used them last sept. for stingray city. for $25 per person, they meet you at the pier and take you in a van to the boat - usually about 10-15 people. then, two guides take you out and stop at coral gardens where you snorkel off the back of the boat for about 20 minutes or so. then, off to stingray city - shallow water, with dozens of boats and hundreds of people. also, hundreds of stingrays. they brush against you and the guides will show you how to hold them and feed them. our guides made sure that everyone got to hold and feed the rays. very personalized service. they give you some fruit punch drink thing on the boat. they do expect tips on top of the $25. you'll have no problem tipping - they provide a great day! I think their website is nativewaywatersports.com. if you send an email, sharon will answer you right away and answer any questions. you also don't have to give a credit card number, which many companies do. Highly recommend them - wish i was going again.
Have also gone with Nativeway and they are great! One thing you often get stuck with, with no way to know in advance, is a large group. Bummer. Nativeway was a small group -- more help, less crowded feeling, more ability to see what you're after, etc. Loved it!