I noticed on most of the MGM properties there is an option to pre-book early checkin for a fee ($20 - $30). Prices dropped for our dates @ MGM. Called in to cancel and rep told me she could make the adjustment vs cancelling & rebooking online for no charge - yea. I mentioned we would be arriving on an early flight for short stay and wanted to add the pre-book option. She told me: "there is no need...a room will be available". I'm not adverse to trying $20 trick when we do check-in (even though it appears not much luck since we'll be in a grand room) but really would like to be able to drop our bags, freshen up and hit the ground running. Should I take the rep at her word?