I'm looking forward to this despite the mess that was Big. I love the feel of the posters, and the Korean title is such a good pun that my dork self can't help but be excited.
ETA: I hope the poster of So Ji Sub and his reflection is meant to be a subtle jab at the fact that the man only ever has one expression. Especially when compared to Gong Hyo Jin's poster where her reflection is smiling back at a gloomy GHY.