I made a trip to Vegas during the holiday season, Dec 25-29 to be exact. I planned on playing at the Aria for at least 2 days I was there. When I got a chance to play, the waiting lists were very long. My suggestion is if you want to play cash, arrive early if you are looking to put in some hours because it is a very busy poker room. I put my name up for both 1/3 and 2/5 and waited nearly an hour until I was seated. I sat at the 1/3 table and had fun. I was fortunate to sit with sociable players and the dealer was also very friendly. After about 5 hours I left. During that 5 hours there was never an empty chair or table. The Aria staff were good at filling games quickly. When a tournament table broke, they quickly filled it with a game. It's sage to say there is always action at the Aria.
My next day playing at the Aria, I tried out the 7pm daily tournament. They have a great structure starting with 10,000 chips, blinds at 25/50 and 30 minute levels. There were roughly 70 people registered for the tournament. I was talking to a regular and he said there were usually more players but that night there were so many cash games that they didn't have more tourney tables. I did fairly well but ran into a cooler. We all know how that goes. I would play in an Aria tournament again on my next visit.
Overall I enjoyed my time playing at the Aria. I would say the waiting was the downside but there is nothing anyone can do about it. The Aria Sportsbook is right next to it so you can kill time there. I do recommend this poker room to all players. You will not be disappointed.