i saw a guy buy one of those at the Oakley store in a mall in Denver. i couldn't figure out why he wanted it... coupled with the goggles that attach to it, he looked like a tool.
oakley made that specifically for slipknot. they made one for sid and a bunch of hardcore death metalians wanted one, so they are now making more and selling them.
a shop near me had one of those on display, the manager figured anyone who would buy it would just get it for decoration - like postmodern art or something, the shop was selling it with the mannequin included.