I've put about 120miles on them so far adding to the 300 they supposedly already had. Of those 120 its been mainly flats with some short climbs. Before taking the pictures I already wiped them down with cloth and water, but went ahead and wiped them with rubbing alcohol without much difference(or any that I can notice). What's your opinion on that surface wear, 50%, 80%? Can I keep riding them without loss of performance until carbon fibers are hanging off the side? Should I consider asking for compensation from ebay seller? As I was under the impression they had barely been used and brake surface should be better? It's only like this on rear drive side, other brake surfaces seem okay but getting there.