Buying a gopro! Which one should I get?

This summer, I plan on doing many things that I would love to have a gopro for, I'm just not sure which one to buy. I don't want anything to professional like the Hero 4 Black, but I do want a good camera I can use for things such as whitewater rafting, biking, hiking, sports, snorkeling, etc. Should I go with the Hero 4 silver, or would one of the older models work good for me?

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