The one I got for my Bally Rolling Stones fit perfectly and I don't need any tape or anything to hold it on. The gameplay is actually better with the protector in place than it was without it.
I wanted to try one of these for this particular machine because I installed an NOS factory-assembled playfield that I had in the original wooden Bally crate. Brand-new and never used. Plug & play.
The only problem with a playfield like this is that it has a few minor sunken inserts and because it is an NOS assembled playfield, I didn't want to strip it and have it clear coated. It is only original once and the use of these protectors allows you to keep it that way if you want. I can always remove the protector and the playfield will be all-original again. Can't do that if you clear-coat it. Clear-coating is irreversible.
I can always strip the playfield later and clear coat it if I want but for $100 the protector was a nice way to protect this very-rare mint playfield from wear while enabling great gameplay.
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