This is undoubtedly a good bit and I gave it five stars on that account, but consider what purpose you're buying it for. It is characterized as a “plunge” cutting bit, and it will do that, but not as well as an up-cutting plunge bit will in certain situations. This because the bit throws chips sideways in a mortise, rather than evacuating them from the hole. An “up-cut” bit (usually solid carbide, three times as expensive) will pull the cutting chips out of the mortise and will allow a deeper plunge than you can get with a straight sided carbide bit like this one. If you're intending this for dados, wide floating tenon mortises or shallow ones, there's no issue because there's enough room in the hole for the chips to go. However, in narrow, deep mortises of the type you might use in a face frame or chair making, you'll only be able to plunger about 1/4” per plunge before removing the bit from the hole and manually cleaning out the hole. If you don't, the chips will clump together inside the mortise and begin to burn. If you're using a jig with a collar, they'll clog the collar. Any bit of this design will do that. I didn't understand this simple design issue when I bought this because my main motivation was saving a little money, however when I had to plunge a large number of deep, narrow mortises for floating tenons, the limitation shortly became apparent.This bit will join my collection and in future be used for plunge and straight cutting, and for narrow, deep mortises I'll buy another, a solid carbide, up-cutting bit intended for that purpose. I recommend this one for its correct use.
Rating: [5 of 5 Stars!]