I understand this question was about Roadster brakes but I thought I would chime in. I have an 05 classic that I bought new. I have been annoyed at the rear wheel brake locking up. I replaced my brakes at 25K miles with OEM pads for about $175 for the front and rear. But I decided to try cheap brakes to see what I could do about the lock up. So at 47K I installed Volar kevar/carbon pads. The entire set cost about $40. As expected they do not have the grip of the OEM brakes. So, you need more foot on the pedal for the rear brakes. This has virtually eliminated the rear lock up situation. Previously my rear wheel would lock up with just the slightest touch. I had two experiences when I needed to panic stop and the rear locked and I went wobbling down the road. Had to let up on the brakes to save it. I don't know how fast they will wear out but I don't care at this price. These brake pads fixed the problem. I might go back to the OEM front pads but never again for the rear.
Part # Front VBP 196. You need two sets
Part # Rear VBP 151
I got them on Ebay.