My advice on the Sharpmaker is that you absolutely must also purchase the diamond stones for it. The included stones come in two grits: Extremely fine, and unrealistically fine. It's capable of sharpening only 30° combined and 40° combined angles and nothing else whatsoever. If your knife is already one of its built in edge angles it is capable of making it worryingly, dangerously sharp in extremely short order. But if you need to use it to bully a knife into either of those two angles to begin with that's not a task that can realistically be accomplished on its included stones. I've done that exactly twice in my life, and the process was rather more akin to some manner of obscure monastic penance ritual than a sharpening job.
"Disciple! Two thousand lashes on the stones!"
It takes hours. Forget it. You need the diamond stones, which are still pretty fine but are at least theoretically capable of removing material on a non-geological time scale.





