Rio believes that building a solid partnership with Vidic has helped the team reach the top of the league this season.
"We've never really had a settled back line since I've been here. I've played with numerous different people.
"Maybe I had a settled one with Mikael Silvestre, but even then that was interrupted a little bit through injury. I think now is the most settled it's been, and now we're getting our reward for that."
"We've got a good understanding of each other's games," the 28-year-old said. "We're always learning. He's willing to learn as well. He's eager to learn the game and he's doing that at a great rate at the moment.
"It's fantastic. But the other pleasing aspect of it is that we've got people waiting in the wings. If there is a slip-up or a drop in form or an injury, players such as Wes Brown, Mikael Silvestre, Gaby Heinze are more than capable of stepping in, and John O'Shea can play centre-half as well. That's good, because competition for places is vital for us.
"Consistency is the key. That's what I've been striving for throughout my career. Experienced people such as Alvin Martin, Iain Dowie and Slaven Bilic had that consistency when I was at West Ham; and that consistency comes with age a lot of the time.
"I've gained a lot of experience over the years, and I'd like to think that's been paying off in my performances of late."