Britney Spears and Demi Lovato showed two very different styles on the red carpet at last night's (Dec. 20) 'X Factor' finale. The result was the same -- both were gorgeous.

Brit Brit was all dolled up in a black Bottega Veneta gown with a bustier bodice, YSL heels and Neil Lane earrings, so she mixed black and bling. The dress dipped low in the back and showed off the superstar's tight tush. You could bounce a quarter off that thing.

Brit's smoldering, smoky eye shadow and deliberately disheveled updo completed the classy yet still-sexy look.

Lovato went more casual on both nights of the finale, even though a bevy of swank designers would have loved to dress her. Last night, she reaffirmed her love for British store Topshop, wearing a turquoise and copper micro-mini that hugged every curve, paired with black platform stilettos, which she also tends to favor. It was a glam look, which she completed with basketball-sized hoop earrings. But we expected a little more razzle dazzle from the stylish star. We wonder if she caught Niall Horan's eye, since his band One Direction performed and his flirtation with Lovato is oft-discussed in the blogosphere.

On Wednesday (Dec. 19), she also went more casual in black leggings, a tunic-length top, blazer and heels. She was a knockout as she played with volume. She wore her chocolate-hued hair in loose waves both days.

PopCrushers, who looked better? Brit Brit or Demi? Or were they both smashing and stylish?

Frazer Harrison, Getty Images
Jonathan Leibson, WireImage / Frazer Harrison, Getty Images

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