Yes, it's a chinese airsoft knockoff but...uh...it's a piece of plastic? If it "fails" who gives a crap? Anyway, it (apparently) will snap onto the US classic stock, but needs trimming at the front to clear it in the "most collapsed" position.
If you'd like to pay 250 bucks for the swiss part, knock yourself out.
ETA: Pics of the riser in question on a classic (not mine):