I did like it, but I wouldn't like to watch it again.
For the story, I felt that it was dragging too much sometimes, especially in the middle of it. Although it is worth to be patient until the end. I've done it and I don't regret it.
For the casting, my favorite characters in the whole drama are Kim Yoon Soo prosecutor, Kwak Young Jae, and Ki Myeon Joong. Honestly, it's worth to watch it because of this 3. The 3 actors did a great job to impersonate them.
Music of it wasn't bad but it didn't make me listen to them besides the drama.
Overall I give 7 because of those 3 characters, 'cause they are worth to be watched.