No wonder I'd never heard of these. Seems like the vendor caused quite a ruckus with his antics and put a bad taste in people's mouth regarding his product.

I saw Dr Matt's video. I've also seen Keith V. Johnson's. 2 experienced honers, 2 different rocks, 2 (very) different results. I've also read reports of them being everywhere between. Highlights the fact that naturals aren't made in a controlled environment. Each hone will be an entity unto itself with it's own quirks and foibles.