the inserts will last a long time, if Craig says 20 hours ask on what kind of material, I turned 15, 8 inch Ash handles today and 6 yesterday and the insert face I started with is still pretty sharp, Ash is not a fun wood to cut, I start with a piece 1-5/8th square and you can see what the handles look like here. I think a fairer assessment would be how fast and hard are you cutting, and how hard is the material you are cutting. JMHO. the Woodchuck inserts are great or I wouldn't sell them!!