I bought four CBN wheels on Amazon direct from China, 80, 150, 400 and 1000 grit, $299 each. I'm using Bora Gold fluid. I am a pro, I'm working farmers markets and doing pop-ups and some restaurants. I usually have 20-30 hours of work a week in season, I've lost count of how many pieces I've sharpened. I wish I had the CBN wheels from the beginning, I went through three stone wheels, struggling to keep them true, getting uneven results (although my customers have been very happy with my work all along.) Stone is great for small volume, not acceptable for high volume. I am working much faster now than befofre. I have had them now for four months, holding up beautifully. I figure Vadim worked with this factory for his wheels, but they offer fewer than he did, two with round shoulders and two with square.