What would Britney Spears and Justin Bieber sound like singing together?

Apparently great! Thanks to the voices of Artie and Blaine on Glee, you can get an idea of what the two superstars would sound like together. Check out their mashup of “Boyfriend” and “Boys”.

If that's still not enough Glee for you, click HERE to hear the cast of Glee do “Call Me Maybe.”