Ziplining is fun, you have to embrace your fears and put your trust in the ability of that cable to support you. We went in Puerto Rico and loved it, I'd definately do it again now that I have a better idea for how it works. I liked my tour company and that they had a double line for safety..  The tour guides, jokingly, said that the second line was a back up; if both lines went down that meant Karma was reaching her hand out to bitch slap whomever had been bad.. bwahahaha..