Jeff, I just realized the picture you mean--those other stones were at the shop I got it at, not mine. Well, one of them is mine. The other was a big Oohira that was more than $1000...*sigh*
Fair enough...I have another that's pretty much identical to this one, though this one is a touch grayer. I'll test it...maybe...if I can stand to take the stamps off.
If you can work some slurry on an area with no stamps, honing over the stamps will not erase them for a while, unfortunately the label is in the way..