Quoted from KenLayton:
The fact that previous "The Pin" machines aren't even on Stern's website nor have any manuals/schematics ever been issued doesn't exactly instill confidence in these machines. These machines, just like any other pinball machines, are going to break at some point and need a technician to repair it for the machine owner. It is vital for a technician to have the necessary information at his fingertips (switch matrix, lamp matrix, coil wiring, driver transistor numbers, etc) in order to make repairs quickly and correctly regardless of whether it's in the owner's home, or even in an office or waiting room.
Wonder how detailed the manual from the coin box is?