Quoted from Aeolus7:

Been collecting a while, but just had my first NIB experience. One thing I didn't expect to see (but makes perfect sense) is dust on the game. A new game may have been sitting in a warehouse or on the production floor before getting boxed up. So I'd recommend giving the playfield & cabinet a good wipe with a new, microfiber towel. Maybe even spray with an air can to get dust of the mechs, etc. Once it was clean, I waxed the game on Day 1.
I also went around the playfield and checked for loose components or screws, made sure everything was tight. I actually found an orphan washer inside one of the scoops and was able to grab it out with a long, magnetized drill bit.
Don't do what I did and install the wrong number of balls, lol. The game called for 4, but came with a 5-pack and I added all 5 in my excitement to play. I managed to confuse the game and thought it had an issue until my buddy realized what I did wrong...