Alex & Sierra Put Their Love to the Test With the Newlywed Game

ETONLINE

The duo put their relationship knowledge to the test with the Newlywed Game.

Real-life couple Alex & Sierra not only won the third (and ultimately final) season of The X Factor USA – they stole the whole show.

From the moment this duo took the stage with a stripped down version of Britney Spears' "Toxic," it was clear: this was the act to beat. Now, they're prepping to release a debut album filled with brand new, original tracks. Among them: The duo's debut single "Scarecrow," which they performed on the Today show earlier this summer, and "Bumper Cars," which debuted on Monday.

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The Florida natives stopped by ET's Los Angeles studio recently for a chat about all things music, relationships and songwriting.

Alex & Sierra open up about writing a new song with John Legend just as "All of Me" became a smash hit and about how their relationship has changed since auditioning for Simon Cowell's reality competition.

"It hasn't really changed at all," Sierra Deaton mused. "I guess we see each other more often."

Alex Kinsey was excited about one particular perk of their new lifestyle. "We get to go to a few more nice dinners than we used to," he said with a smile.

But when it comes to mixing business and pleasure, the couple says they are just happy to be making a living together with what they love.

"We work really hard, but it's such a fun thing to be doing together," said Sierra. "It'd be really hard to, just as soon as we leave, get in an argument over something 'cause we've just had so much fun."

We decided to put their love to the test with a Newlywed Game-style interview. So just how well do these lovebirds know each other? Watch the video above to find out. Below, ETonline has exclusive video of the duo performing their new song acoustically.

"'Bumper cars' is a song about trying to make a relationship work, but the stronger the effort, the further you push the other person away from you," the couple told ET. "It's a back and forth tug of war. It's about fighting through tough times and putting together the pieces of something that means the world to you."

The song was written by Steve Mac and Claude Kelly, and produced by the former. It will be featured on their album It's About Us, out October 7. Compare the acoustic version to the studio recording, below. What do you think of the new song?

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