I recently received an inquiry from a customer who was thinking of purchasing the 15mm wide 30K Shapton Pro Edge Pro stone, and I thought that sharing my answer would be helpful to others.

In order to experience the full potential of the Shapton stones, the 30K is a must, in my opinion. The 15mm wide 30K Shapton Pro EP Stone is certainly a luxury, though – I won’t try to say it isn’t. In my experience it leaves an incredibly consistent and very smooth, yet gripping edge that is not duplicated by any other method I have tried.

Can other things arguably do as good as or better than the 30K pro? Yes. However, different products yield different results. 0.5 micron Chromium oxide makes the bevel very shiny, but the edge becomes less gripping, while 0.5 micron diamonds make the edge more aggressive and leaves more scratches on the bevel. Furthermore, there will be varying results based on the quality of the Chromium Oxide and carat concentration and shape of the crystals in diamond sprays and compounds. These variations are by no means negative if a particular product or combination of products produces the results you desire. I wholeheartedly recommend you experiment with the different products to find which suits you best.

I do recommend the 30K if you are serious about sharpening and your budget permits it. The 30K completes the Shapton lineup, which is the original intention behind using Shaptons. They are designed to be used all the way up to 30K instead of switching to another medium like pasted strops or felt pads at the end. As mentioned above, switching to different products at the very end produces different results. I happen to really like the results of the 30K specifically for sushi knives and straight razors.