Yeah, it is pretty dark.
Another Korean movie I thought was OK was The yellow Sea. If you like The Yellow Sea then you might like The chaser. I was not a fan of the latter, but they are similar movies.
I'm pretty much going through every Korean movie netflix has available for streaming. So far I've liked most of what I've seen with "Perfect Match" being... well, I haven't finished it but other than the female lead constantly getting tripped, falling or getting her face stuck in an automatic door the movie has been pretty predictable and boring.
If you find any other Korean movies that you like please share here as I want to see as many movies and hear as many songs as possible. The language really intrigues me (especially its origin) so I'm trying to learn it and the movies help a hell of a lot more than the music.