Production, acting and OST were mostly good.

In terms of acting, I must say Choi Myung Bin, the girl who plays young Lee Hwi and young Dam Yi, was amazing! I believe she has a bright future as an actress.
Also, actors Park Eun Bin, Bae Yoon Kyung, Jung Chae Yeon, Yoon Je Moon, Baek Hyun Joo, Kim Jae Chul, Bae Soo Bin, Kim Taek... They were all great!

I believe the story could be told in way less than 20 episodes, though. It is an interesting story, unpredictable and made me very curious. Romance and friendships were sweet and heart-warming for the most part. Family relationships were also interesting.

There were too many flashbacks, slow motion scenes (romance parts) and the fight scenes were very, very repetitive.

Overall, I enjoyed watching this show! It's not for everyone though, it really requires patience.