First of all: not suitable for serrated and cheap stainless steel knife. Steel-quality knives are so sharp as bought. Ceramic knives are sharpened also excellent, smaller outbreaks and nicks Vedas eliminated, but the focus is not quite enough to connect with the original, but is better than if you try it by hand on a diamond stone. It should be noted that the material when sharpening is quite high. So go with little pressure and a sense of proportion to work. It can not be edited, the whole blade length for most Messren. Near the specifications usually 10 to 12 mm remain unpolished. The sharpening process itself requires a little practice, the best procedure by ear. It is worth to a billgen Allerweltsmesser to practice before going to the good stuff. Sharpening is really fast, I brought my arsenal (15 St) in a half an hour to scratch. If you like ultra-sharp knife, must rework on a sharpening stone by hand.
Conclusion: a very good device for the kitchen. I do not want to miss it.