A word of warning Andy
I have playfield protectors fitted to my Jungle Lord, Flash, Warlok and Bally Playboy
I would have fitted one to my Alien Poker but they were not available for that game at the time - I will be ordering one now
In general I'm very pleased with them
They solved the problem of dished inserts on my Jungle Lord, stopped the deterioration of the poor paintwork on this era of games, were easy to fit, look good (like a layer of clear coat) and in the main don't affect play in any noticeable way.
I do have a small problem with the Warlok one in that I cant get the shooter lane "tongue" to align correctly, so shooting the ball was causing it to jump and return to the plunger every time - I added a a bit of mylar which has virtually cured that
HOWEVER
In the course of a single league meet the playfield protectors seriously damaged the driver boards in both my Flash and Warlok
What happened is that the protectors moved slightly during play (they are not fastened down in any way - they just sit on top of the playfield) and this was enough to cause the pop bumper skirts to get caught under the protector, causing them to be permanently "on"
If it had happened with just me playing, I would have noticed this, but in the noise and bustle of a league meet it went unnoticed until smoke started billowing from the games.
Not only did the coils melt, but the driver board transistors got so hot as to burn and blacken the boards so badly that it took out the flipper circuits as well. It is possible one of the driver boards is damaged beyond repair.
This is due to a design flaw with older Williams games where there is no specific fuse protection for the special solenoids (pop bumpers, slingshots, etc.)
It is a well documented problem if you search on the internet
Therefore when you fit your protector I STRONGLY suggest that you add in fuse protection for your pop bumpers.
You can either do this yourself by adding in-line fuses to the wiring, or there is a more elegant solution here:
https://nvram.weebly.com/repair--conversion-kits.html#
(you may be able to find these at a European stockist I'm not sure - I did buy a few of the kits from Peter Koch of Inkochnito when I was in Holland)
I'm aware that the thickness of playfield protectors has been reduced since I bought mine, so it may be that this is no longer an issue, but to be honest I think these fuses should be added even on games without a protector since there are other reasons why a pop may get locked on, and it is far better to lose a fuse than a board!
Finally to say - this is also an issue with older Data East games, as you can see from the service bulletin they issued:
