Cap Mata stones?

[HeavyHanded]

Anyone have experience with Cap Mata silicon carbide sharpening stones, in particular the 500 grit one sold by Machete Specialists? I checked out the company a bit and they offer SiC stones as high as 1000 grit for rubber tapping knives - I didn't think SiC could be fused into a useable stone at that grit.

Trying to find out if the 500 grit would be any finer than the fine side of a Norton Crystolon stone.