from the Ebay store description:
Factory refurbished products are returned (or open box returned) product that have been refurbished and certified by Polk Audio to match Polk’s performance, functionality, and reliability standards of new product. Refurbished products may have minor cosmetics blemishes and/or imperfections. The manual and accessories are included with most of our refurbished items. Cosmetic blemishes and imperfections are not covered by the warranty.
To focus on some minor blemishes and expect a definitive answer of all imperfections possible is unreasonable.