I love everything about city center! I've stayed in both aria and vdara and both hotels are amazing!
Everything is definitely up to date and I like how there is a connecting bridge to the cosmo and planet Hollywood. Every easy to get around.
The only complaint I do have is upon checkin we requested to get a two bed bedroom instead of a one bed. The lady at the front desk said it would be 30$ extra a night, which was fine. We get our keys and when we walk in there was only 1 king sized bed. We called the front desk and they quickly switched our rooms. They even sent someone up to the room to give us our new keys. *definite plus*
Aria is apart of M life so if you have a card use it for the parking. I think I saw somewhere that they comp your parking or something...not too sure though. But it's only 10$ per night and you're allowed to go in and out.