Plan on 2 to 3 hours depending on the size of your family/group and their comfort level on the ziplines. Take a camera; wear walking shoes or sandals. In two words, "Amazing Company"
We were a group of 9 people ranging in age from 6 years to 46 years. Only two members of our group had ever ziplined before so this was all new for most of us. We were joined by one other zipliner and 4 guides. The guides split us up into two groups of 5 people each with 2 guides between us. They started us off on their Tarzan Swing. Instead of pushing everybody to do it, they asked people to volunteer and only had us do it when/if we were comfortable. They were super patient -- a great start to the morning. Before we got on the ziplines, one of our guides asked if we wanted to hand her our camera so she could take pictures of us. As we zipped to the end of the first line, she called out, "Smile, you are having fun, aren't you?" and "Click." She got amazing footage of us.
This continued throughout the trip. At one point, she said, "I am taking a video" and she proceeded to take some great videos of us coming in! We knew we had made the right decision coming with them when our middle son, who has a massive fear of heights, came off his first zipline and beamed, "This is fun!"
They were so good with all the ages in our group that on the next day, half our group decided to come back to them for another round. The other half decided to go to 100% Aventura hoping to try something different -- this was a bad decision as describe on the 100% Aventura link.
Back to Original and the 2nd visit -- this time, my 73 year old father-in-law joined. He had never ever ziplined before and had such a fantastic experience that at the end of the Costa Rica trip, when asked what he liked best, he summed up, "Canopy Tour."
I highly recommend Original Canopy Tour of Monteverde to anybody who wants a fantastic experience with superb guides, personalized attention, and great memories (photographed by the guides).