As you all know I'm perfectly happy with the edge I get off my Sigma 6000 stone. I've never seen the need to go to a really high grit but I recently bought a Japanese natural stone from a Dutch site (I'm Dutch) that sells second hand tools. It was only €70 (that 78USD) so I thought, what the heck, lets see what this thing does to my knives. It's a hard stone and somewhere in the 12.000 grit range, that's even higher than my coticules. I took it with me to work today just to try it out on my chisels and well, I'm converted. You were right Derek, it does indeed make a difference. I'm going to keep the stone with me at work and use it as the final step after the Sigma 6000.