Most people will say pish-paw but a Sinar or Linhof selected lens (whether from Rodenstock, Schnieder, or Nikon) is definitely worth more than a stock lens, just as a Calumet branded lens (Caltar) from the same manufacturers is worth slightly less. Accordingly to Bob Salomon, Linhof and Sinar have purchased expensive testing equipment from Linos (Rodenstock) to do additional quality control checks on their lenses.
Few mortals can afford to purchase a new Sinar or Linhof lens but on eBay the lenses are only $50 more than the standard lenses, so if I see a good deal I'd definitely opt for the named lens - besides, you'll get it back in resale value.
Good buy on your part - congrats