I watched this because I love Jang Nara, but I was worried (dramas prior to 2014 make me worried) because it might be problematic and strange.
Although the plot is cliché, the acting between all four leads is good. Jang Nara and Jang Hyuk offer chemistry and are in their elements as their characters. The second leads do well on their own.
If I have to complain about something is the length - it could have easily been a 16-episode drama, or maybe even a 12-episode. But that was expected given the relatively simple plot and it being a 2014 drama, as the story goes on and on until everyone reaches a complete happy ending.
I did throw fits against Sera and Daniel, so I have to say I >>really<< didn't care about them in the end. But the central couple made everything worth it and it's definitely in my top 20 dramas.