I had ordered my AnySharp due to the positive reviews and überwiedgend'm really disappointed. My old knife sharpener worked with several, interlocking carbide discs and brought a much better sharpening result than the two ceramic plates in AnySharp. A straight akzeptabelen as "success" I had with the device only with thin blades. Once the blades were thicker failed the device. Serrated I have not even tried. Well, the suction cup, he keeps on a glass ceramic hob really good and you have your hands out of the danger zone.