edit: I saw this pointed out in another review and remembered I also wanted to say this.
This series treats almost all female characters pretty badly. Either they're portrayed as awful people (cold, hateful, bitter and bitchy), or they're "the few good ones" and their cool fighting abilities suddenly vanish. (of course, how else could they be saved by the male protagonists?)
The "awful" women also tend to change their personality entirely once they fall for a man.
And listen, I do enjoy a tsundere who will punish the protagonist for being a snarky little shit. So there were a few characters that did this kind of thing and I liked that.
But overall the women in this show are not handled well.
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As many other cdramas this is way, way too long for its own good.
The show has issues with pacing at the beginning and towards the end.
The overarching story is stretched too thin and it just doesn't support itself over 44 episodes.
You very quickly realize what has to happen at the end and then you're just expecting it to happen. Everything in the middle is supposed to be character development and a few training arcs.
But there's not that much development and not that much training. Some of the smaller story arcs are fun, but aren't amazing on their own and do little for the overall plot.
There is some nice foreshadowing, establishing of characters and setting them up for future events.
The fights are not as common as you might think and they vary in coolness.
Having only seen one other adaptation of Handsome Siblings (the 90s HK movie which is wildly different), I can't say if the issues I see lie with the material being adapted, or the adaptation.
There are a few uncomfortable plots and characters, but nothing too terrible.
I have to say one of the most villainous things one of the main characters ever does is chew with his mouth open. All the time.
Truly, the evilest man alive.
It's not awful, but I expected something better from a classic of the genre.