[For the benefit of Internation readers, "Bonce" is a colloquial English term for "head".]
I've given this bone bonce 3 out of 5 because the price is nice. The quality, however, is rather poor. The removable top barely fits the bottom so, to turn it into a horror prop (as my work often calls me to do), you'd have to work in some kind of horrific brain-removal scenario or, alternatively, spend a day in the workshop filling and sanding the pieces to make them fit.
Objectively, though, if you just want a cheap bit of skullage for a medical demonstration, this is fine. Some of the teeth are removable, too!