Alex & Sierra and Andy Grammer decided to perform a mashup of each other's songs and release it on YouTube, as a way of reminding fans that their co-headlining tour, The Good Guys & a Girl Tour, is about to kick off. They do a perfect job reimagining each other's songs and blending them together so seamlessly. Let's not even get into just how fantastic their voices sound together. It kind of makes us wish they were a supergroup of three, instead of two different acts.

Andy starts off the medley by performing his own version of Alex & Sierra's song "Scarecrow," and then Alex & Sierra perform Andy's song "Sinner." Our favorite part has to be when all three of them are singing at once -- they may be two separate songs and are two totally different artists, but the mashup definitely works and does a fantastic job proving how well-suited they are as artists to each other. If you weren't too keen on going to their tour before, you definitely will be after watching this video.

Their tour is set to begin on Feb. 24 in Seattle and will end on April 3 in Los Angeles. Andy will be promoting his sophomore album, Magazines or Novels, while Alex & Sierra are touring in support of their first full-length album, It's About Us.

Check out the video above and let us know what you think of their medley! If we had it our way they'd both re-record each other's albums in their own styles. How cool would that be!?