birdsandspurs...initially I bought a 4.0 but sent it back after determining, at least to me, I wanted a bit more zoom; thus I waited for the 5.0 to come out and bought it. Besides, if I want less zoom I can always adjust that with the app. Not to say the 4.0 isn't great, because it is. Regarding video quality..even though it's 4K capable...I shoot at 1080P 60 fps. Both my PC monitor and TV are 1080P so videoing at 2.7K or 4K gains me nothing. Regarding using a GoPro, or other video camera, I'm with Fullfan. I've seen GoPro videos of turkeys in that 25-50 yard range and they look like hummingbirds. Same applies if you use it for deer hunting...gotta have zoom. As far as gun mounting that's fine if you want to point your gun at whatever you want to video. Personally I don't...that's why I made a good cap mount...I didn't care for the factory cap mount. Plus, when you have a bird coming in you can't be moving your shotgun around...they won't like it! But, as you're slowly moving your head you're recording them. I'd far rather have it such that whatever I'm looking at is getting recorded; of course the shot still gets recorded and the recoil doesn't pull you off your video target.
Edit: Perhaps I need to post a pic of the hat mount I made...works great.