The angle is "only" 332.8° at a diameter of 350mm and a width of 5cm, so one break shoe has a length of more than 1m and in total it sums up to an area of more than 0.2 m square meters on all breaks together.
The best thing was, that it was completely evenly used (down to the rivets). I haven't tried the remade break yet, but I guess it will be really good.