You should have no problems going from an 8k to the Suehiro 20k. It's an easy stone to use, and the edges are exceptional. I personally go from a Naniwa superstone 10k to the SG 20k, have been doing it for more than two years. The edge is clinically sharp, some people's skin doesn't tolerate the acute nature of its finish, but for me it's a great stone and will last for many generations. It's a terrific touch up stone. I find 6 strokes on the SG revives a razor completely.