Definitely cool.
I wonder, would the lower function properly as-is? Could you put a regular, un-modified upper on there and safely shoot? I can't see any reason why not, but I'm no expert.
The auction listing does say "designed to be fired" so I guess it should be fine?
Yeah the gun itself would function just fine as is, the suppressor on the other hand might not be as desirable to shoot.
I hope that "suppressor" doesn't transfer on a form 4 and isn't actually considered a suppressor.