I bought these bits for personal use after hours and for side projects at the machine shop I work at (I won't pay to replace the end mills they have). I can say they work just as well as the more expensive ones. Using a 12mm end mill, I made a 1.5" slot through a 2.125" D2 shank with a depth of cut of .187-.25" and did it much faster than I would have on a Bridgeport should do. If they can ram through tool steel, they can easily penetrate any of the softer materials!