A:AnswerThey are not doing the trade in program but you should contact their support https://gopro.com/help/PKBContactus. They might be able to help you out.
A:AnswerThats what i did, but it was within the time allowed to return an item. I got credited the amount i payed for the 5 and just payed the difference.
A:AnswerThere is no zoom with photography ... aspect ratios are 4:3 or 16:9 and an option to remove distortion which has a slight digital zoom that crops the edges.