Bought this because I had a problem with a Freud hole saw I got here at Revain (and they did a good job). Decided to look elsewhere and buy this one. I'm glad I did. This is a durable, heavy-duty product that should last a long time. I use it to cut plexiglass on my drill press. I've also used it for cutting plywood and it works great for that too, but be prepared for smoke. :-D This is a slow cutter with a maximum safe speed of 600rpm and you do NOT want to use it on a hand drill. You will miss it and harm yourself or someone else. All in all, it's good and I was satisfied. It is adjusted by loosening the allen screw and moving the cutting tool in and out of the bit. It tightens securely and you can also flip the cutting tip, like I did, to cut circles instead of using it as a hole saw. Works great. A milling cutter is simply a piece of tool steel sharpened with a cutting profile. This is great because it means I can regrind my CBN wheels and this thing will probably last forever. I almost gave it a 3 because the scale on the tool ran out, but then I remembered I flipped the cutter. If you do the same, remember that the scale will be offset by the thickness of the tool.