First off, I have to say that the actors and actresses did a phenomenal job. Son Ye Jin never disappoints with her skills as an actress and the supporting cast did great as well.
I'd say the drama does a really great job at portraying a realistic scenario and relationship. Without spoiling I did not like how they resolved things. If it had ended a few minutes earlier it would have been poignent and mature, but it felt somewhat cliche the way they closed it.
My main issue is that for a drama with a minimal budget like this, they still could have edited better and not shown a majority of the actors and actresses from behind their heads. It was extremely frustrating not to see people when they were talking for long periods of time. Also- be prepared to hear the same three songs every episode at least one to three times. I literally never want to hear "Stand by your man" ever again. The editing, filming, and repetitive music (to an extreme) soured what is an otherwise actually good drama