The room is great, but honestly the best thing about this unit is the host Colette (6 stars). I have never experienced such an attentive and available host. She responds to messages and requests so quickly, that you'd think it was a computer on the other end. But it's not, you will be in very good hands and can feel comfortable about your stay.
As for the room, if you like Game of Thrones, it's really fun. They went all out on the decor. We sent lots of pictures to friends.
The kitchenette was well equipped and we were able to eat in the room for a number of meals. I almost wish it wasn't, so I could hit up even more of the Vegas restaurants. It was VERY clean on our arrival and check-in was quick and easy. Very comfy bed, good shower and an Iron Throne for a toilet, what else do you need? I've stayed in almost every casino hotel in Vegas and this one is better any of the 4 stars, but it's not the Wynn or Cosmopolitan.
If you like valet parking, it's easy & free (just tips). Parking got a little backed up at rush times, but it was never full. Tower 3, where this room is, would close early so you would need to come in at tower 2. Just a 3 minutes walk though so not an issue, but partial cause of the backup.
My only complaint is that the MGM Signature and MGM Grand no longer has umbrellas at the pool, except for reserved chairs ($130) and cabanas ($170). That goes for the entire property. So if you require shade, be prepared to pay for it. At least the cabanas are a fraction of the cost of other hotels.
In summary, if you are looking at rooms at MGM signature, I would choose this one over any of the others. Why? Colette.