Funny thing is I wasnt comparing the "plastic to metal" bizz until you brought it up. Had you read the rest of what i said, youd have noticed I was speaking about the smooth construction of the inside of the MS one as opposed to the cut straight edged construction of yours. But while we're on the subject, arent most aftermarket suspension pieces like bushings, etc. made from polyurethane, as well as many others even apart from automotive pieces all made to endure weather and beatings?
Pretty sure nothing would happen to either scoop. Dont know why this would ever even come up, as long as they are set in and installed correctly, nothing will compromise their structure unless you crash into something. So metal vs polyurethane is no argument over which to buy. That said, half of our cars' interior and engine compartment makeup is of plastics, plastic has come a long way.
Do what ya want eh? Ive said my piece