For the playfield, I have used carnuba paste wax only, use a micro fiber cloth to buff the wax off. Avoid using polishes/ cut polish, they contain abrasives. To test for abrasives, put a small amount on your finger, then rub your thumb into it, you if you feel any grit at all, I would not use it. Apply the wax in light coats, two or even three coats, instead of one thick layer. Some people use the new High Tech polymer finish wax, these usally contain silicone. I am not sure if it is ok for the playfield. I would avoid the old style green liquid Turtle Wax Hard Shell. The old Turtle Hard Shell sticks easily to rubber and plastics and can be hard to remove. Just one guys' opinion.