I have asked the reviewer whether there is any vignetting of the picture due to the lens protection.  Otherwise it looks very good, and the additional metal should - perhaps - help with dissipating heat.  The magnetic mounting feature is lost, but for extreme use, maybe that's inevitable.  It seems to be a Chinese product and is available here in Australia on eBay (but sent from China).

Hello there. Good day and thank you for sharing this information and video about a DJI Action 2 metal case. Nice find and thank you for your support.

Nice find!

Looks good.   

Great find.  

I've now been assured that there's no vignetting with this case.  The main drawback is that it's not light.

I feel there are better cages in the works by the likes of SmallRig and Tilta.