Hadn't seen this post, sorry. The answer is somewhere in the middle. It's been a while but I think that the ones in the Rue picture were show only. We did do some carbon rotors that worked....to a point. We couldn't find a brake pad that would work without squealing. The quietest running pads were made from carbon fibre as well, but the heat build up was too high for regular riding. We did consider further testing but there are now some super light alloy ones that were so close in weight to the carbon ones, it put us off developing the disks. The best rotors we did had carbon centres with an alloy brake track, but the weight was close to 100 grams, so they looked good, but were fairly heavy in a lightweight world.