Quoted from CrazyLevi:Are the brains of that thing really stapled to the underside of the playfield?!
That seems like a pretty bad idea. Playfield vibration is enough to knock solidly soldered wires off of coils, can't imagine what it will do to transistors and chips over the years.
I saw that pic and thought exactly the same thing. I can picture surface mount devices falling off the pcb over time. A coating would solve the problem but then its a pain to do any repairs.