I bought this tool to cut grooves for several exterior doors that I have made. When I cut the first one, I was amazed at how quick and easy it went through. This is not my first vertically cut helical drill bit, but it is my first CMT drill bit - Whiteside was my "choice". For reasons I can't explain, this one just flew through the entire work and there wasn't a trace of burnt wood left when I was done. It was like, "Is that all you have? Come on get some more!' I'll definitely be trying more CMT bits.