Yep, Choi Min-sik was the principal actor in both films, he's also the lead in Happy End, a very different restrained performance, probably his scariest performance. He's also the lead in Chihwaseon as the artist Jang Seung-up, again a different performance, a brilliant artist but a drunken womaniser with more than a touch of arrogance. 

Although I've had Address Unknown for a while, I haven't had (or made) the time to watch it yet.

Cheers Trev.