"Worn" is probably not the correct term. Broken teeth might be better.
If the slides aren't synced from the beginning, they can get slightly misaligned which could cause some issues. Who knows if they're running the slide in and out properly on the lot.
Either way, take a look at the track. If its missing any teethe on the track, have a dealer note it so there are no questions when you decide to bring it in.
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