“I think this rifle does not use the “direct impingement” gas operating system of the M16. The lower is essentially the same with tweaks, but the upper uses a proprietary gas piston operating system.”
That’s not novel either, and while I’m not an M16 expert, it seems that many people dont like the piston system and prefer direct gas operation. In fact I was at a gun store recently and the salesman used the fact that a certain model didnt have the piston as a selling point.