When we went, we saw lots of wildlife, including alligators. The drive said that the best time to go was in the morning, before it got hot. We were on the 10:30 boat I think, but we saw lots of birds, taking off right in front of us, and we were about 20 feet away from an alligator.
We really enjoyed it, but I would try to do the ride in the morning. We went to the one that is closest to 192, not the airport. I don't remember which one it was, the east or west.
If you go to Boggy Creek's website, they also have a video that you can watch. They also have a night time alligator ride. HTH