Douglas733
Member
They are a waste of money for anyone with any real use of a chainsaw...for the casual chainsaw user they would be good...but for someone using them for serious work they are not as economical as the traditional sharpening. They wear the chain down pretty quick. The advertisement mentions a sharpening in 3-5 seconds...more like 30-45. Greatly decreasing the life span of the chain. What they would be good for is a quick fix in the field, to save a trip back to the barn or shop. They work no doubt...but cut the life span of your chain to 1/3 or at best 1/2.