Thanks a lot for your reply
I agree that OEM is always better and I would buy OEM Performance diffuser, but I like CF more...
I want smth that look similar to vorstainer, but not that expensive. I think price for vorstainer diffuser is too high... it is almost the price of two OEM rear bumpers. And vorstainer is also aftermarket, but I havent heard anything bad about it.
And as you probably now, local BMW dealers dont sell carbon fiber rear diffusers