I figured this would not really be able to get a burr off a blade as with traditional stainless it can be hard to get it off even with a normal stone. How could a rubber stone get any burr off? I’ve had the sparx for over 3 years now which I love and have never had issues but when the black steel came out I had to use a piece of wood as to not damage the coating. I’m not sure the science behind it but when you sharpen black steel(I’ve done bladetech, step, LS5’s and the new LS Pulse TI’s) for some reason the burrs are pretty easy to get off so this is perfect with a couple swipes. Sometimes the toe will be a little harder and I’ll really have to go at it but usually it’s all quick and painless. Been using this since about a month after it came out. Highly recommend.