I was always slightly intimidated about whetstone sharpening and the risk of messing up the angles on my expensive knives. This angle guide was a perfect investment - it helped me ensure my hands were holding the knives at the right angles and was effortless to use. After doing a handful of knives I found my hands almost naturally trained on that angle and feel so it might not be something I need to use long term since all of my good knives are the same angle.