I've had this hone for about 4 months and honed/touched up about 3 dozen razors with it.

Mine was not affixed to the base and so I have been using the "bottom" side to leave the stamp untouched.

I have found that the amount of swarf produced seems to vary from quite alot (for a 20k) to virtually none. The resulting keenness of the edge seems to vary as well.
I always lap with an Atoma 400, and it is definitely faster with a bit of slurry left behind, but I have not found this to improve the keenness.
I have tried using the 3k/8k rubber that came with it and this dramatically increases the swarf production, but I am nearly convinced that it is simply embedding coarse particles in the stone as the edge always seems to be set back when I have tried this.

Now, yesterday when I was lapping prior to touching up a couple of razors I noticed that there is a variation in the colour, a white band 5-7mm wide has formed on one edge and there is a hint of one forming on the other. The center region of the hone is very slightly yellow, and looking with a loupe I can see a mottled appearance. I need a better camera to show this, it is very subtle.

My thought is that I need to keep lapping and see if the center region continues to shrink. Judging by the chamfer on the edge, I have removed about 1mm since receiving the stone. The peculiar thing is that I feel like I had better results with the first few razors I honed.

Has anyone had similar experience?