Bought these to replace a B&D diamond coated disc which despite being half the original size still works. Also, those 10 disks are now equivalent to a B&D disk, so think about it. I've just used one for wood and metal stapling work and got the job done with no breakage or unusual disc wear. One star deducted for not being the CHEAPEST but there really is nothing wrong with being the next cheapest as long as the product is quality. Qualitatively, if they prove to be as durable as the B&D rims, they'll be a hit, but I can't say that yet.