This is an absolutely incredible tour -- our guide Jason was both very informative and very helpful. He explained the history of the Arenal volcano to us, we took a short hike a small part of the way up the mountain, and then went back down to look at wildlife in the rainforest. We saw spider monkeys, which Jason said are a pretty rare sight, and then a red curacao just walked out onto the trail in front of us! It was an incredible feeling to just be seeing all these animals spontaneously on a nature hike.
Speaking of hikes, it is important to be aware that this tour is somewhat physically demanding. There are no extreme parts, just some strenuous walking over very uneven ground, but I think the tour description could do a better job of emphasizing the challenge. At the same time, the tour is extremely convenient in terms of picking you up and dropping you off at your desired location, whether a hotel, hot springs, or somewhere else. Overall, I strongly recommend the Arenal Volcano trip to anyone who is into volcanoes and wildlife and plans to visit the Arenal area.