The good.

Loved the lyrics and the singing. The actors are a pleasure to look at, especially Byun Sung Tae. I could gaze at that dreamy face all day long!

The confusing.

There are at least three characters introduced with some depth and we (the audience) start caring about them. But then there isn't any more. The viewer is just left wondering. As an example, Lim Ho Yeon (surfing instructor) cares about the main character (Lee Seung Jun). He appears in quite a few scenes, and we see what he is feeling. He seems like more than a side character, yet we never get anything satisfying. Same goes for certain behaviors we see. As a viewer I want to know the "why" behind these behaviors. But we never get the why. So it ends with the audience unsatisfied.

The bad.

There are portions in the last half that are just meandering.