Received this unit as gift this Christmas. I found it to perform as portrayed. It brought several knives, mostly serrated ones, that were sitting in the drawer for 20 years back to life, and restored an edge on a couple of Japanese knives I have been using for a year. Turns out that there are two types of edges (single / double) on those Japanese knives, and unfortunately the manufacturers don't tell you which, so you're left with eyeball examination, which for me was tricky. But the bottom line, given the Amazon reviews, and this being my first, it seems to be a great sharpener. It does take a lot of passes to change an American edge to the 15-degree edge but so far it seems well worth the effort. READ INSTRUCTIONS!
I had been considering a belt-driven, shop type sharpener that Amazon sells, there are two models, and they sharpen everything, tools, sizors, knives, shovels, etc. I'm not sure any powered kitchen sharpener would perform as well as those models in the right hands.