I bought these for drilling 100 1/4" diameter holes in galvanized steel pipe where oiling the bit was impractical and I did it didn't want to risk "good" drills. I figured there was a pretty good chance I'd end up breaking the edge of the cutting face, chipping, or just snapping the whole piece a couple of times by drilling the Hole hitting the concave inner surface. on the other side of the pipe Aside from some scuffed finish and a spinning shank on one of the bits (which still cuts well), I've had no failures with these bits. Seems sharp enough. They're not all super even from one bit to the next, but they're more than enough to make a lot of imprecise holes in steel.