Hello guys,
I didn't expect this, but DJI actually managed to probably beat the biggest Action Cam maker at their own game... but it kinda seems so.
I have compared the specs, image and some videos showing stability in my article review over here: https://dronesgator.com/dji-osmo-action-vs-gopro-hero7-black/

If you'll check the article, the last video is a short stabilization comparison done between these two and the Sony FDR, byt Iphonedo and it's absolutely incredible.

Which one do you like best (no fanboying around, pelase)?

Thanks for sharing

Nice work!

Nice comparison of the tech specs and a lot of work put in there.  However for me the real test is whether the footage is actually usable when using it as an action camera (ie mounted on something (eg surfboard, ski-pole) etc and filming yourself in an 'action' setting. It is after all an action camera and I think that is part of how it should be judged.   I just bought an Osmo Action and was really impressed with it compared to my GoPros (Hero 3+, Hero 5 Session and Revl Action cam) in terms of specs but my initial action footage was really disappointing.
I used Rock Steady and the cropping is so severe that either my feet/surfboard are cropped off or my head and shoulders are.   With the GoPros much wider angle lenses and the Revl's lens (along with its single axis gimble) this was not a problem.  
It's a durable, rugged camera for sure and the quality of it and its footage seems more than adequate for my personal use but it fails badly for action footage where it is mounted on or near the subject because the lens is far too narrow.
I regret purchasing it now and will probably replace it with a new GoPro unless DJI can do something magical like offer a replacement wide angle lens.
Cheers.