These cutters are pretty good, better than the other style. However, they could be better. I found that the drill bit in the cutter doesn't do much drilling and will skip around. To get these to work, I suggest drilling a pilot divot. Also, the 3 that came with my kit didn't go dull but broke off one or multiple cutters making them useless. Even with cutting fluid. They can be sharpened and used again but the blades cracking off was a pain.
Rating: [3 of 5 Stars!]