The "cons" of an overlay greatly outweigh the "pros" - unless you want to hang the playfield up on the wall !
Pro's
Better than a playfield with bare wood
Looks good
Con's
Plays much slower than a mylared playfield. I played a KISS with an overlay and I had to check to see if the back legs were elevated high enough. It played like an EM. Really disappointing. I played a Space Invaders with an overlay, and then mylar on top and it was unplayable.
Playfield inserts are cloudy and in most cases, lacking registration. You need very bright lamps as the light has to penetrate the inserts and the overlay
A lot of time and effort goes into preparation. Would equate to around the same time for a professional to touch up and clearcoat the original playfield
Will eventually wear out, and you are back where you belong - probably even worse as you had to sand away the remaining art to have a flat surface to apply the overlay.
I considered overlays for my KISS and Playboy machines - but having played games with overlays installed - I would keep well away from them if you wish to PLAY the game. As an "ornament" - they are good. I've opted for my playfields to either be restored and clearcoated - or - replace them with a repro from Classic Playfields or IPB (I have 6 playfields already). Most of my games will have repros as I intend on playing them !
