The Rio is a must to stop at when you're in Vegas.
The buffet is awesome, they have something for everyone.
In the masquerade side of the casino they have a show on the hour after 5 with real singers/dancers (not lip syncers). And they throw mardi gras beads out during the show in the sky. (Really cool)
The bartenders even do a bottle spinning show and whoever screams the loudest gets frees drinks/shots.
Totally fun and a surprise (I thought it was going to be depressing and run-down)
We will be staying here next time if I can get a comp.