Hope it does well for the guy but at $20 a pop on cover he's got to break $120.
Part of the problem with PDF is that if you just want the material, that's still available.
While I've seen the first one for sale at those prices I've listed one for trade for well over two years and never gotten so much as a inquiry over it.
It went for $117.50. The seller didn't quite break even on it.