I was really excited to hear that the Rio was opening a dim sum place as I have tons of comp points built up and love the traditional dim sum experience.
I've been there 3 times now and it's been about a 2-2.5 star experience. The food was good the first two times that I was there. Very traditional dim sum fare. The most recent time that I was there, the Har Gow was terrible. No shrimp. Just this ground up white looking "meat" that kinda tasted like chicken.
Service was terrible each and every time. It was chaotic and the management doesn't seem to care. Also if you you sit on the far "stage right" side of the room, you will not get any food except for the crappy items that no one wants as the carts start on the other side of the room and always run out of the good stuff before it gets to you. They go back and get more food but then start on that side of the room again.
I'm giving up on this place. Going back to Beijing Noodle No. 9.