Overall, it's not bad. I'd say if you like the characters, then I don't see any reason not to like it, as it's basically all your normal k-drama fare stuff here. Reason I'm not a big fan is because I didn't like all the characters. I really could not stand Jo Yi-so from beginning to end. I couldn't find a single likable thing about her. Considering she is one of the two main leads, I just had a harder and harder time caring about this show as it moved forward. Honestly, my feelings toward her were borderline hate. I have nothing against the actress btw.
Park Sae Royi was fine, but it all honesty nothing special. He is your basic sturdy lead who is supposed to be the all around perfect person everyone else looks up to. Nothing to dislike about him, but at the same time not super interesting. I'm probably more negative toward him just simply due to him being paired up with Yi-so.
It's nice and all that the show tried to add some progressive elements with Toni and Hyun Yi, but I feel like they could have done more, especially with Toni. For once I would like to see a foreign looking character be born and raised Korean, to stick it in all the racist faces that will only accept them as being foreigners. But yet once again they fail to do that here by making Toni just another one of these characters who has never even lived in Korea until a year previously. Nor was he even a registered Korean, which only proved the annoying Yi-so's point that he wasn't Korean. I appreciate the try, but I hope the writer can push things a bit more progressive next time, and not just what felt to me as just surface level.
The one thing that kept me going through this show was the revenge plot. It was entertaining and I enjoyed Yoo Jae-Myung's dastardly villain. And for better or worse, I did really like Nara in this, even though the show had to go and do her wrong, but she is a secondary lead so what else is new.