Could have done with just 2 bits, but I carelessly twisted and truncated one. Nice and sharp, I stacked 4 1/4" oak veneer sheets with an MDF backing, used a sheet of perforated board and a parallel guide, I was able to drill about 2,000 1" deep holes in each drill bit before they started to feel a little blunt. I cut one of these off after about 90 holes because I was in the middle of a project that required drilling 4000 holes and was a bit lazy so I'll attribute it to user error.