If you want the best, pay around a ton for Mattig cup mirrors. They do about 5 or 6 different kinds of mirrors that are all top notch and subtly different from the Halfords specials you see around. Cant remember who distributes them, but I got a set and they are the nuts, totally smooth, each baseplate is perfectly formed and the mirrors flow smoothly off the baseplates, no sharp edges or anything, top German quality all the way.