We wanted something fun and exciting to do for our anniversary trip that did not involve climbing a mountain. This was an excellent choice. The zip lines were a lot of fun. I have a fear of heights and thought it would be terrifying, but it really wasn't. It is 100% safe.
My only complaint is that we were told at the end of the tour that gratuity was expected and that they only took cash. Given what we paid for this experience, this hidden 'fee' was unexpected. Additionally, like many people, we don't carry much cash. A simple credit card reader attached to a smart phone would have saved us some embarrassment and allowed for our guides to be well-tipped. The expectation of gratuity should be noted somewhere on the website, registration forms, or in the Captain Zipline office. Anywhere but at the end of the tour with no ATM in sight.