Recently got the KME system to augment my whetstones and various other sharpeners. Haven't really used my whetstones since I got the KME. Still learning some of the tricks of the system such as using it on a short full grind knife with a fat belly (Esee Izula and Izula 2). There's a little challenge getting a good centered grip even with the pen knife jaws but I think I'm getting the hang of it. I did get the strop kit and the lapping film kit just to try the differences. Haven't taken one to a full mirror yet but it didn't take very long to take it to the Band-Aid level (don't ask) even before using strops/lapping. It's a fairly idiot proof system if you take your time, still much faster and less messy than going through all the whetstones. Most people will probably never need anything more than the basic kit. Knife nuts will probably want the deluxe kit, pen knife jaws, strop or lap kit, convex rod and the diamond serrated rod. Even with all the accessories it's less expensive than a lot of the other basic systems out there.