Karl Lagerfeld SS10:
I think both sets make for striking images, especially when you see them in magazines. Haven't seen the KL ads yet, but the Chanel ones definitely stick out to me because of their insistent brightness. Interesting that Karl would choose to go completely dark for his namesake brand. I think it's rather fitting as I've always thought KL had a darker, more severe (in the German tradition) type of aesthetic message. And since the same two models are featured, the use of light and dark serves to develop a much needed distinction between the two brands. Although, if forced to choose, I'd probably go with the KL ads. I love how Freja and Baptiste's faces stand out against the black. And those ads really show how well they can work together.
Image Credits: designscene.net, my scans