Ehh, this is such a disappointment. I don't even know where to start. KHJ is a terrible actor, his acting is too stiff and one-dimensional compared to many of the other actors on the show, he also seems to have the weakest character dramaturgy-wise, all he does is look angry or has a blank expression on his face. Jaerim too can't act and always plays the same character, the plot is too predictable, editing is really odd — you don't even see any real action. Relying too much on editing to cheat its way through the fight is my biggest complaint. This is seriously missing some seamlessly shot fight sequences that put all of the action in a single, two-shot frame. Instead, the action is broken up and filmed at such close proximity that it can be difficult to see what exactly is happening. Of course, this is to disguise KHJ's lack of any real martial arts skills, but overediting shots so that you can never really see what the fighters are doing isn't very interesting to watch. And damn, those overused music soundbites whenever there's a suspense/emotional/romance moment. They took it to the extreme. Oh, and what's with all the Japanese characters speaking Korean? Couldn't they hire someone who could speak Japanese? Or are Koreans that lazy to read subtitles? This is a lot like IRIS, it's got great budget and everything but it's still garbage.
I may write a longer review at some point, but it's probably not worth the time.