LIKES:
Action right in first episode
Decent fight scenes
Writing:
No romance thrown in, because it didn’t need it.
The bad guys didn’t upgrade to guns.
The bromance between Gun Woo and Woo Jin was fun and heartwarming.
I liked the young archery character and her dynamic with the two boxers.
Production:
for the most part was good, sometimes zooming camera in too close, but at least shaky camera wasn’t noticeable.
Music:
was fitting, but no song stood out.
Cast:
well selected and I love that Woo Do-Hwan is a main lead. (Both boxers were delightful eye candy!)
FX:
blood and scars were decent.

DISLIKES:
FX:
the stitches looked to be done by a butcher and not a medical professional. Some of the facial damage, like broken noses were omitted. The big facial scars should’ve been a little more raw looking, compared to what was shown.
Directing:
Pro criminals not noticing a car tail gating them on an empty highway and following them every turn they make?
The elite bad guys seem to be able to handle a lot of force on their heads, which throws the realism of the fights out the window.
Writing:
A few characters we need more information on what happened to them, especially at the end. However I understand why they had to get rid of Kim Sae Ron’s character due to the actress’s DUI, but the way it was done made no sense due to the character that was created up until that point.
The whole Marines part about the two boxers: Marines are trained in hand to hand knife fighting and many other weapons. The South Korean military are trained in Teukgong Moosool. Their characters knowledge and skills therefore very lacking.
Criminal element was very unrealistic, especially since the master villain gets defeated by two young boxers. Also all the masters (the brains and brawn) get defeated so simplistically, which made for a disappointing conclusion for their characters.
A lame plot was covered by violence.
Pacing issues:
Ending felt rushed, but they had plenty of extended drinking moments. Time could’ve been used better.

OVERALL: The fitness level that the main actors had to achieve was awesome. This should've been an action movie and not a series. It's fun to watch for the fights, but don't expect anything from plot. I don't need to watch it again, maybe just clips of the 2 boxers (lol), I would recommend it for fight scenes and action only.