Have used playfield protectors on a few which have been great, only thing I have noticed is on some games the ball can bounce back off posts into the air. Does this happen with hardtops?
Fish Tales and Taxi have the bounce back air balls. After buying a FT playfield from CPR recently I will try and save the originals where possible.
Did this with Taxi recently using a playfield decal kit and protector. Looks great now but has some annoying post airball bounce backs.