I bought this sharpener to keep my screwdrivers that I use for clock/watch repair in good shape. They are by nature small and if you get a stubborn enough screw (or your wife borrows them for she’s working on) they will twist at the tip or even chip an edge.This sharpener has done a great job with A) getting them back into the shape they need to be in by using larger passes and taking time to ensure it’s done well and B) keeping them that way by using smaller, lighter passes after every few uses.There is a bit of a learning curve if you’re not familiar sharpening things on a stone. I’ve been using whetstones and oil stones for years for my kitchen knives and such and I tried this product out on a couple of my cheaper Chinesium ones to learn it. The guide works well, you just have to make sure the screwdriver is set at the correct angle and straight in the holder. Using many light, smooth passes without a lot of pressure I was able to get my screwdrivers perfect.My only complaint is that there isn’t really a way to use the whole block and through enough use, the stone will eventually start trenching. I made a frame about 1.5 inches all the way around the stone to be able to utilize more of the stone and hopefully keep it from trenching as badly.