This is a great option to get out on the water for a first-time experience exploring the Keys. Check in is fast and online (no filling out paperwork), the equipment well-maintained and the spot is in a good location, right off the highway and next to cozy little spots to grab lunch afterwards. Our kayak tour was small (7 people) which makes for a nice manageable group. We kayaked alongside dolphins and saw crabs, jellyfish, nurse sharks, herons, egrets, pelicans and plenty of fish, including a few tarpon. One surprise was that we spent the first half of the tour cruising residential canals rather than the mangroves.
Our tour guide was super friendly, helpful and eager to make sure this was a great day. She took a lot of photos of all of us, which documented the whole experience in a really nice way. We didn't see any manatees on the water but one happened to be resting in the marina when we got back. We were all thrilled to see one up close!
Tip: It would be helpful to give the group an overview before leaving: show us the route on a map and explain the basic 'rules of the water' before you're out there. You may also want to give beginners get some practice time before embarking as a group.