This is a good set of useful size Forstner bits at a great price. These are simple steel drill bits that will need sharpening after heavy use - there can be dozens of holes in pine, but only a few holes in OSB or something very hard and abrasive. Mine had clearly visible burrs on many of the cut edges. After taping the edges to a wooden spatula with 320 silicon carbide paper, the bits held up fairly well. However, due to their rough edges, they may not give great results. Please note that the maximum recommended speed is 700 rpm.