Prestige = Unlimited visits. (Select simply excludes CO/UA lounges after 9.30.2011, and has nothing to do with the number of visits. A membership can be both Prestige and Select.) Some banks do absorb the cost of guest visits. It sounds as if Chase has agreed to do this for the memberships issued through this specific card, but you should seek verification from Chase customer service, or simply use a lounge with a guest and see if you are billed. (The lounge attendant knows nothing about the details of your membership or billing.)