This was one of a few adventures we went on during our brief stay in the Arenal area. It was only my wife and I and another couple. Honestly, there wasn't much of an adrenaline rush as I thought it would be but rather more relaxing. The tarzan swing was really fun and that's what did it for me on this tour. Other than that, it was platform - zip - platform - zip - platform...with views in between. My experience with it may have been hindered because I was worried about the braking/stopping in time (it was emphasized quite a bit during the training zip line) rather than enjoying the faster paced ones.
The staff was great. Their English was good, explanations were informative, and were willing to help you every step of the way.
Overall it was a lot of fun but nothing over the edge - at least for us. Granted the views and the experience itself made it worth it but I suppose I had expected more out of it?