This is a great drill. I bought 7mm for drilling blanks for handles. It is perfect, very sharp, very durable and cleans the flute of sawdust very well; although some hardwoods like cocobolo will get tough if you try to drill through a 2" piece without clearing it about halfway (you can go all the way, but the flute is pretty much exactly 2" wide). Overall it's perfect for my needs and at a good price for this quality bit I will be buying more. I've only drilled about 20 pieces so far, both hardwood and softwood, ebony, cocobolo, cherry, elm, padauk, black walnut and purple heart through to soft maple, red cedar, spanish cedar and all that. with excellent results and without Much effort. If there is any unusual wear or if it doesn't last as long as the previous bits I will come back and update this review.