Plastic is cheap enough that I would not mind replacing them every year.The problem would be to find a plastic that wouldn't get scratched up after a couple of weeks of use.
Now, who is that guy that is making various accessories for model S?
Like center console, lighted Ts, different nosecones, ... there is idea for another product - full moon wheel covers. Make them 18" and I'll buy them even though I'm still MS-less.