Absolutely the worst paying slots in Vegas..hands down. Want a "free" beverage? Forget it...you will die of thirst first before a server comes around. And, yes, like many I was just in line with....buying a beverage cause servers on the floor are akin to unicorns. Way to save money Rio...oh yes we wont be back, way too many other service oriented casinos in Vegas.
Update:
Wow was I wrong Rio, 50 minutes in, and we actually flagged down the server...for a beverage....
Final addendum. Steve the casino manager came and made things right. Great customer oriented manager.