Thanks everyone, the discs look a bit cheap, I don't generally use cheap brake parts! Better quality discs tend to have much better machining. I noticed the discs have heavy spots, probably not going to be a problem unless it causes vibration. I did have a run out problem when I purchased the car, it turned out to be hubs, I purchased new ones from James Whiting which cured the problem, they have less than 0.02mm run out. It shows that JWM don't have much faith in their products! although that could just be the usual legal stuff to cover their backs from people fitting stuff with any idea of what they are doing. I notice the caterham discs are £169 each! does anyone know which vehicle they sourced from?