Nope, actually I haven't even seen Infernal Affairs just providing proof that there are non super-hero movies in Asia. Have heard sooo many good things about the killer and is definitely on my must see list on imdb. In the last 2 months I've really gotten into Asian movies and have seen a bunch including Old Boy. This movie is amazing, check out the trailer. Also saw Ichi the Killer recently but that was almost too weird for me.
Old Boy Trailer
http://www.cinemas-online.co.uk/trailers/OLDBOY_FF.mov
Ichi the Killer trailer (warning some adult content in it)
http://www.ichithekiller.net/trailer/trailer_high.html
Those are both in Quicktime, and the Oldboy trailer really doesn't do the movie justice. I could also see Oldboy being nominated for best foreign film at the Oscars this year for Korea.
Oldboy
Ichi the Killer