Justin Bieber & Kelly Rowland Do 'X Factor UK'

Justin Bieber and Kelly Rowland were the celebrity guest performers on Sunday's results show of 'The X Factor UK' (December 4th) - The teen pop star performed his hit Christmas single "Mistletoe" while the former Destiny's Child member treated the UK audience with a medley performance comprising her global dance smash "When Love Takes Over" and new RedOne-produced single "Down For Whatever". Enjoy!

Did JB overuse the adlibs?
Kelly murdered the stage, but did she wow vocally?