Colour-wise, I would say it compares to grade 5. There are some other Blancpain watches where the grade 23 is polished and indistinguishable from stainless steel at a first glance. Blancpain have given this Fifty Fathoms a satinated finish which has a soft silky appearance in real life. The effect is most pronounced on the bracelet.
592 Blancpain listings are live on the eBay market and 179 collector listings on the WatchProSite marketplace.