I've never been particularly effective at sharpening knives, that is, until now. For nearly a decade I've used replaceable blade knives and in my opinion they still have their place. However, since receiving my Work Sharp MK.2, all my old knives are once again an option. Within a few minutes of reading the instructions I had knives that were paper shaving sharp. Filet knives, hunting knives, kitchen knives, pruning shears and even a metal credit card have been sharpened to shaving sharpness. I've also tried touching up some of the replaceable blades (Outdoor Edge and Havalon) to extend their life with fantastic results. I've since purchased another to keep in my camper and one for the shop as well. You simply can't go wrong with this sharpener.