I have a GoPro Hero 3 and 3+. They are ok, but I have software problems and SD card problems with both cameras. The battery life sucks, so I have to carry a bunch of spares. Besides that, I think they are good. If you really want to film a hunt, you need a real camera. The GoPros can give a unique point of view, but you lose the detail and close ups provided by a real camera.
I have filmed a bunch of hunts with mine, and much more fishing. I am still figuring out how to film a hunt so it looks good, but I am getting there. I have used it mounted on my head, the gun, and the boat; all provided mediocre results. Some cool POV shots while looking down the gun barrel at geese back peddling around 10 yards. Body mounted gives too much camera shake for my liking. My best setup was putting it on a stake about 5 yards into the water this past weekend, right on the waters surface. It gave a great POV, and no camera shake. This weekend I am going to mount it on the back of my layout boat, elevated high enough so when I sit up, I do not block it. This should give a sweet POV of birds working in tight, and watching the shooter shoot.
My best hunting settings are 1080, 30fps, medium FOV, WIFI off. This gives about 1:45 of continuous film. The medium FOV will cover a 30-40 yard radius in all directions forward of the lense. You can clearly see birds working, committing, and dying, provided they are inside of 30 yards. Species ID is tough, but it does look good. Low light performance is excellent with the 3 and even better with the 3+. I turn it on right at LST, and we were shooting ducks below the treeline 5 minutes after, and you could see them work and die.
I wish it had better battery life without the battery bacpac, I wish it had a quicker way to get filming, like the VIRB record slide, and I wish they would fix the software and SD card issues. Still, I feel that GoPro has the market cornered for now. I really love the cameras for fishing applications, above and below the water!
GROUND POUNDIN THEM GEESE AND ARKANSAW'N THEM DUCKS