I had a cube of the soft stuff. A friend sent me a cube the harder version as he didn't like it.
The first time I used it, I got a little on my shaft and hand. Instantly stained the shaft, and when I went into the wash room after my game to wash it off my hand, water made it set in like a nasty dye. Water only made it worse.
When I die, I will have an antique cube of Kamui to leave in my Will.
Why anyone would pay that much for a cube of stain is beyond me also.