Although I didn't like the way the writers changed some parts of the story from the original manhwa (like the way Na Il Deung quit school instead of going to the university, and the way he didn't decide to meet up with Ah Yi in the last scene, which kind of changed his whole ending), it was a really enjoyable experience. It was truly magical.
The acting is immaculate, and the OSTs are so good. To be honest, I didn't expect Ji Chan Wook to sing that well.
Also, the message of the drama/manhwa is so important and cool. I would really recommend it.