I think this video is worth a mention. He is explaining things using the GoPro but easily translates over to the Action 3 as well. (...aside from where he is talking about the kool and free FW updates for the GoPro...)

Good video indeed!

Very good summary of what was discussed in several threads here. Nice Video.
I find it very interesting, that the footage of the GoPro 11 shows exactly the same artifacts that many people complain about when coming here. It shows the same jittering that is predictable when using slow shutter speeds and EIS, it shows flashing edges on branches and foliage because of oversharpening and high contrast. Nothing, I didn't expect or fear, but I don't own a GoPro myself and had no comparision (and don't care).

Nice find and thanks for sharing.  Very informative video.