We recently had a 12 person outing with Backwater Adventure. All in all, we enjoyed ourselves, the Craig Cats are pretty cool once we get the hang of it. You will get wet at times once you hit the Gulf waters, but its all good.
If I had one criticism, the "tour" felt very "follow the leader" and had zero substance. Mostly just driving around, following doug, then we get to the stopping area, we sit around for a bit, then we head back. There was a very quick dolphin siting once at the island, but that was very "matter of fact", like "hey look there are dolphins..." those that didnt beach yet got to go around them, others did not. Maybe this experience was because it was a large group. But I probably wouldnt do this again. I have done other 10,000 island tours and they were a much better experience (and they were with 6+ water craft as well). Please take my criticism as a "room for improvement" and not a negative. It was still a good time!