When talking about this drama, I could tell that it was soooooo beautiful, that my heart kept aching every minute, throughout watching it, and that it is a dangerous panda eyes zone:), and that for days I kept walking around with a broad smile on my face whenever a really funny scene came back to my mind.
I could praise the actors, the main characters as well as the supporting ones. Because they were brilliant each one of them. (it was real fun watching here Ha Neul as a cute garrulous hillbilly, after seeing him in Moon Lovers, as an intellectual politician. Even his voice was different).
So no big deal, since many of the Kdramas have those attributes.

But... and here comes the most important thing, the writer was a genius.
The most meaningful conversations in life are very simple but weighty by their truths. Just think about it, how many times have you been left with the "aha" feeling after a talk with a friend, parent, lover, that wow - he/she is so right, and wow - now I have learnt something? And frankly, you do not meet those weighty words so often in life. The sad truth is, we tend to be superficial and corny. If you talk to old people, and ask them what exactly did life teach them, you will get only a few sentences, as a gist of their life experience. And then I ask myself, this is what you learnt in 70 years?
But in this drama, the dialogues were so lively, touching, witty, very simple and so true at the same time. And those simple dialogues showed us, what is important in life. One can make as much fuss about psychology as one wants, but we humans are very simple. We need reliable loving parents, friends, and a lover that we can lean one. And we need GENUINE ones.
Those dialogues written by Im Sang Choon are in a way similar to the "Dialogues of Platon". He too wanted to teach people using Socrate's conversations, to reveal and explain the truth. Im Sang Choon does the same, teaching us how to live a good, meaningful life. I don't think that anybody can give more valuable advice to another person.