In short, yes! There are many good brands that have graphene as a part of
their formula. But that is the crux of it, GOOD brands.
Making a graphene car coating is not as simple as adding cheap graphene oxide
powder to a vat of silicone dioxide (often marketed as SiO2) based coating and
calling it a day. Some cheaper brands do this, and the tell-tale sign is that
the graphene has precipitated at the bottom of the mix. This means that the
graphene has not been properly mixed in and leaves you with a basic coating
with inferior protection.
To properly make a graphene coating, the graphene has to go through a complex process of being infused into the coating. Where the result is lengthy, the results speak for
themselves. The solution will often come out clear, as the graphene is nanometres
wide and has been dispersed throughout via the infusion. This is actually
beneficial as you want the paint to truly shine under the coating. Otherwise,
the car would either be speckled with black, if not completely covered in it...