Jennifer Lopez looked breath-taking wearing her Lanvin Spring 2010 dress to “The Back-Up Plan” London Premiere during April.

She really got into the spirit of her Lanvin look by also styling her hair like the models who walked the runway.

A Lanvin necklace, black satin Ferragamo heels and a Jimmy Choo ‘Cecile’ clutch completed the look.

Rihanna wore the same dress to dinner at AGO restaurant in Hollywood this week.

She’s still sporting that bright red hair colour and I hate to admit that it’s slightly growing on me.

The singer only paired her look with nude heels.

I think they both look fantastic and both deserve to win, but I’ll give this to Jennifer as I loved her waist defining leather belt and statement necklace.

Who wins this for you?

Credit: Style.com, PacificCoastNews & Getty