As much as I like the idea, a bunch of questions pop in my head.
"Won't budge on your countertop" because of a metal base? But the metal base is only 2.5" wide, whereas the weight of two boards plus knives is distributed evenly upward at nearly 11". Why wouldn't a gentle nudge send the thing falling?
How do the knives attach? Do they just slide into slits on top? How wide is the slit? Will my thicc knives slide in? What's the length of the slit, or are they separated into multiple slits? When the thing inevitably falls over, will all the knives fall onto the floor and kill my kids?
Are the boards treated with anything?