Actually, an engineered plastic stud makes a lot more sense to me than steel and I have sold steel all my life. But then again, I know about some of the "mystery metal" that gets passed off. Those structural columns in your basement fit that category. For that stuff, no manufacturer cares much what the chemistry is or what the real thickness is or even if it is the same thickness around the tube. Today, the metal studs are still so new that the manufacturers are keeping a pretty good watch on them but eventually, the quality will deterioriate. And there is no doubt in my mind that plastic studs can be made better. The only question is can they be made cheaper.
Of course, I do drink Dr. Pepper when I can get it.