I really enjoyed this drama.
Nice chemistry between lead, overall very good story but 52 episodes is far too long, half of it would have been great.
[Spoilers after!!!]
I found the amnesia (twice) was really too easy, but if you ignore it, it was pretty well used, but not super credible. Some of the supporting roles especially Jo's mother and the mother in law were sometime overacting.
But overall I had good time watching it, some episode were very enjoyable, but too long.