DMT D8EE 8-Inch Dia-Sharp Diamond Whetstone Bench Stone - Extra Extra Fine Grit Knife Sharpener for Kitchen, Hunting & Woodworking Tools | Professional-Grade Sharpening Stone for Chefs, Butchers & DIY Enthusiasts

I have had and used numerous DMT diamond stones for more than 20 years. I have visited the main office in Marlborough, Mass. where they replaced under warranty a stone which looked like it had the diamonds coming off. They didn't think there was anything functionally wrong with it but replaced it anyway, and have me 2 free sharpeners of types I didn't have. They are awesome in my opinion.That said, I think this is a knock off and not a real one because it doesn't look like the same quality as any of the other DMT (have 9, 4 continuous diamond bench stones) products. It looks exactly like you would expect a cheap Chinese knock to look. It looks like it was placed on a concrete floor and kicked around for a while. I looked at it under a 10x jewelers loop and it clearly looks pitted and scratched. The edges look banged up. I included a photo of a 20 year old DMT extra fine grit bench stone for comparison.It's going back. Uncertain at this time whether I will reorder from Amazon who was the seller. I've checked photos of this grit stone and what I think are real ones don't look like this one. They are etched on the side with DMT, Extra Extra Fine, and 3Mesh 8000 Grit. The surface on the photos looks flawless, not at all like this one.Update: DMT terlls me that they have not had issues with knock offs and that these stones do not look like their other stones. I have given it another chance and have learned some things in the process.1) This stone HAS to be broken in. The literature from DMT calls it "partially broken in" at the factory. Fro practical purposes though you need to fully break in this stone for it to be uselful.2) DO NOT USE THIS STONE ON ANYTHING YOU CARE ABOUT UNTIL IT IS FULLY BROKEN IN. (At least as an 8000 grit stone)3) you have to be purposeful in breaking it in. Cover every square inch of surface. If you don't you will, sometime be honing some blade you care about and a part you missed while breaking it in will leave large scratches on it. I took an old plane iron threw it in a jig just to be able to control the surface angle. I was able to flatten out the entire angle on the plane iron. This should not have occurred with an 8000 grit stone. I bought an extra course DMT bench stone because performing this on my DMT course stone was taking too long. I have about 15-20 minutes of contiuous working on this old plane iron and while resurfacing the entire edge angle it is still leaving pronounced scratch lines. It is still a long way from an 8000 grit water stone in terms of honing/polishing an edge. The 8000 grit water stone leaves a literal mirror finish. I judge this to be about like the DMT course stone in terms of how fast and how rough it cuts. The DMT course stone however has been used for years so is well broken in.I will update further when and if I ever get this to function like a true 8000 grit stone.DMT replaced this stone under warranty. I don't of they prepped it more than usually because they told me they do a little prepping on all of them before shipping this 8000 mesh stone. Anyway, the replacement was head and shoulders better than the one they replaced. I'm not sure it's going to get to the point that it will completely replace an 8000 grit water stone. I will update this review of it does.I used this on my test plane iron (which is more than 100 years old and a fairly pitted already so the edge isn't perfect but after using this stone on the bevel and lightly removing the burr from the back, I stropped it with green oxide and then plain leather. It easily shaved hair off my arm. I call that functioning like it should.The big advantage this DMT 8000 grit has over the water stone is that you can just spray some water on it and touch up a plane iron or chisel immediately. With the water stone it has to soak for 15 minutes and then you have to make a slurry using a Nagura stone before you can use it. While the water stone works better in my opinion, I probably won't be using it for touch ups any more.