Tried mine out cutting down about ten boxes after helping a friend move. Found that the piece of sheet steel that forms the pivot/choil is easily distorted. At first the blade started rubbing against the side of the frame when opening and closing, but by the end of the day the pivot/choil was bent far enough that it no longer protected the end of the blade. This could be cured by increasing the thickness of the pivot/choil (and the corresponding spacer in the handle). The Craftsman Superknife knock-off we had worked much better as it had much more support around the pivot area.