These bits are pretty good, better than the others. However, they could be better. I've found that the drill bit doesn't drill and slip much in the router. To make them work I suggest drilling a pilot groove. Also, the 3 cutters in my set were not blunt, rather one or more of the cutters broke rendering them unusable. Even with coolant. They can be sharpened and reused, but the blades will break off.