I've been using Conti's Grand Sport Race for some years now, all from Ali, and it's been great
they're supposed to be 'supplier only', not d2c, so probably counterfeit in some manner. It's the silver ones which are supplied to factories for full bikes, not the yellow printed which are sold directly to customer
anyway, it seems to be the real deal, I've got 9 to 10 thousand km's on each of the 3 pairs of GSR I've gone through. The GSR seem to be the best bang for the buck, but now I'm testing the Ultra Sport 3 which seems to be more on par
it seems that for these cheaper models, it's real, since they're produced in China. I don't know about the more expensive ones, which some models say are from Germany, and for those I'd be concerned it's fake
in Brazil these tires are much more expensive, the GSR I pay less than half if I buy on Ali. For other more expensive models the difference is lower but still significant, so always worth to import this kind of stuff
It seems like it's likely OEM supply. For example, you can buy the Grand Sport Race tyres off Ali which are OEM only - but these are made in China. From what I understand, they're similar to an Ultra Sport 3 but with more puncture protection.