TLDR: MGM doesn't guarantee the room type you book and is unwilling to make it right.
I booked a Skyline Marquee Suite over a month before my wife's 30th birthday. I was thrilled to have a space to entertain the 15 guests I had attending from the local area and also staying in other rooms at the MGM. We planned to have dinner in the large room (with its two living rooms, two bedrooms, and three bathrooms) before heading downstairs.
Upon arrival on 9/17/16 around 4PM, Ricky informed me that they weren't able to honor the room choice and would instead have to downgrade me to a City View Suite (a much smaller room) and a regular room down the hall from it.
I couldn't have been more disappointed. All the planning I had put into the location was rendered pointless because MGM stuck me in a tiny suite that was a joke for the entertaining that I had planned. I didn't have enough places to sit and had to apologize to my guests.
I understand that issues are going to come up but I would have expected an upgrade to a nicer room or a full refund when MGM isn't able to honor my room booking -- especially when it's a $1k+ suite. Ricky said it was due to a "plumbing issue" but forgive my skepticism that this was code for "we decided to comp your room to a high-roller."
The downgrade was bad enough but I was particularly put off by Ricky implying that he was doing me a favor by finding me a room at all. He gave me some money back but was unwilling to provide a full refund on the room that MGM didn't have for me. I didn't have time to find another solution since our guests were already en route (and the check-in process took 45 min). I felt some comfort in that Ricky promised that there would be a door between the living room and the bedroom, but (surprise, surprise) there was no door. I went back downstairs to inform Ricky and still no refund.
I thought about booking elsewhere (I've always had perfect experiences at The Venetian) but I stuck with MGM because I loved this room.
My fault for expecting them to save it for me.
UPDATE: See MGM's response for further proof that MGM won't refund when they can't deliver. Not your fault but not their problem!