Worth the money
The gopro, albeit an awesome camera, only lasts for about 2 to 3 hours of on and off filming. That said, not everyone wants to, or has the time to, charge their gopro battery in the middle of the day. Thats why I would recommend buying the extra battery. takes about 10 seconds to swap out the batteries, and then you're good to go for another few hours of filming. Definitely worth the money.