IUBI, Tangus is right, this is hot and frequent topic of conversation. From my experience I think the Spyderco 204 is a really great sharpening system. It's pretty much fool proof and puts a great edge on both folders and fixed blades. It's also the best thing for serrations. If you REALLY want a high performance sharpener, go for a Edge Pro Apex. Not cheap, but IMO it's the best. If you want to know more, check out my review in the Kife Review Forum. Hope this helps.
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"Better to reign in Hell, than serve in Heav'n"
John Milton
There are only two types of people; those who understand this, and those who think they do.