Black- BoS def. has more fillers in it, it did a great job of hiding on my black truck, the durability is suspect at best I doubt it lasts a month, I saw a dramatic drop-off in beading and slickness after a week and a half, like you I had high hopes for this product, I recieved it as a promo freebie so its really no biggie to me, I still use it once and a while. The nuba though "I" liken to nattys blue, its a light purple/blue color wax with a great scent, not a lot of fillers at all but a great deep shine and pretty good durability, with tight beading. IMHO one of the best buys at Griots for the money, to me its suprisingly inexpensive comparitivley to the rest of the lineup.