Review on 🔧 Straight Chucking Machine Reamer Milling - Enhanced Precision and Efficiency by David Dober

Diameter and concentricity around center hole at tip are very good (near perfect). Mine had SIGNIFICANT runout (in the 3k range) and I didn't bother to check the grind angle after finding out that was probably why I had the most 0.1mm. If you use these things in a hand tool or anything with that much runout, they're probably GREAT. Others have had luck with this and it can happen that the manufacturer's machine occasionally hits the tips and I just got a bad batch. It might also mean that people don't care about 0.1mm on the outside, but I'm not sure why you need a reamer if you aren't going to be using a specific fit.