Expensive, but I have many knives that have 'super steels'. I bought the 1100, 2300 Matrix stones as well, used those first and finished my pocket knife off with this stone to test it out. My pocket knife has CPM S110V steel. It is so unbelievably sharp, I am simply amazed. My knife can shave a strand of hair. It also passed the paper push test, which I was never able to accomplish before. Just pushing the knife on paper, without the slicing motion still cuts. This 4000 stone will give an excellent mirror finish along the edge of the knife. The 1100, 2300, and 4000 Matrix stones look identical so I think it's nice that Edge Pro CNC'ed the grit for each stone on the back for easy identification.
All the matrix stones I bought are of good quality. They hold water nicely and do not require many passes before you can clearly distinguish that they are taking off metal and sharpening. I need to re-learn how many passes I need to do as I can see myself taking off too much metal unnecessarily.
I bought my Edge Pro from PaulsFinest a few years ago and needed some get more extra fine polishing pads. I was excited to see that these new stones are available as they looked promising, and they do as I hoped they would. I made a small mistake with my address and contact with the store was also excellent as I received a response very quickly. Shipping was fast and the parcel was packed nice and snug.
I am not someone who owns a ton of knives nor am I a chef, but I do realize the value of having a good sharpener with really good stones. Yes it is pricy, and yes it hurt to bite the bullet but I believe these stones will last decades if taken care of properly. So overall I am happy with my purchase. I also will continue to make future purchases from this store as well.
I highly recommend the diamond matrix 2300 and 4000 stones for a polished edge. The retractable magnet is a huge asset for holding your knives in place while you change stones or adding water.