Unlike most here my experience with Racer X was not very good.
Bought a pair of Ritchey WCS and NIB Onza Porc II tires.
Rtichey tires are great but the Onza tires turned out to be modern day reissue tires in Porc II boxes. Not what I paid for.
Addmitedly it took me a couple of months to discover the problem, but upon contacting Racer X twice I never got a single response.
Very dissatisfied.