A:AnswerMainly it means items that haven’t got the manufacturer seal on them. It’s in my experience an item that has been used for display at the shop.
A:AnswerThe PS4 Pro represents a meatier, more powerful unit that delivers better performance capable of 4K gaming and HDR. So the graphics are a bit sharper. The slim works fine, just a little lower capabilities when it comes to speed and graphics, not so much to take anything away from your gaming.