I've used a GoPro an a few trips in the parks and find that it is easy to carry, unobtrusive and able to go places you might not otherwise be using a camera (Kali). I have several pics and videos but I also use a DSLR, my phone and a compact point and shoot. I also present info about GoPros at a local dive shop where I instruct, we have an occasional "GoPro Night" for folks interested in the camera. I point out that the GoPro pics have a certain look. The wide angle of the lens will cause some distortion. It can be limited using narrower views (settable in the camera) and some folks like that wide look. I usually use the medium or narrow setting for pics and video which limits the distortion which I prefer on land. Underwater the distortion is generally not as evident. I also usually point out that there is a bit of a learning curve with the GoPro. There is a real benefit to learning a bit about the camera and fiddling with it to get familiar the menus and how it works. I know a few folks who are unhappy with the camera because the assume they can just point and shoot and get the geewhiz results you see in all those videos! You really need to know how to use the camera (and your video editor) to get the best results. You also need to learn something about getting your pics to your computer if you don't already. I know a guy using a GoPro who doesn't even own a computer! He's facing some real challenges using the camera! The videos especially use up memory cards pretty quick though you can transfer to a tablet or cell phone. You might not realize a couple things about the GoPro: 1, there is no zoom on a GoPro, 2, there is no image stabilization, 3, there is no focus control, it's fixed focus, 4, they are not the best performers in low light 5, depending on the model, there is no screen built in and 6, battery life is fairly short, 7, the wide angle makes things look further away, 8, the GoPro App on your Phone or Tablet works well.
The newer models, the Hero4s, have better low light performance and some attractive bells and whistles. I now have the Hero4 Silver which does have a screen built in but other models need the add-on screen if you want one (that includes the Hero4 Black). Previously I've used the Hero2 and Hero3 which used the add on screen. Makes the camera bigger but works nicely.
Here's s couple examples. I have a more in the most recent Disney trips and scuba trips at my links in my signature of you wanna look! For the Philippines dive trip, the GoPro was the only camera I used except for just a couple cell phone pics. Being so small and light, it travels very well.
One with the obligatory selfie stick!