I don't know if it's the BEST, since i've only been on one....we had a very good experience with Boggy Creek airboat rides in July.
We took a private tour, so they used a smaller version of their large tour boats, and we were able to not only tour a lake, but got into small grooves and tighter edges, etc.
We loved the experience and had a great guide who spoke of birds, gators, snails, snakes, etc -
We saw a couple gators, birds, etc, a HUGE spider on a tree that had me going...TOO CLOSE, can we back up!! LOL
We would happily return there, and I'm sure we will at some point in time.

wear sunglasses...if you're going fast, those dragonflies will bounce right off of you!