I do like korean shows, and this was supposed to be a top tier one, at least with choosing top rated actors, the effort that went into the effects, the music, and the story. Sadly the last bit sank really deep.
I love sci-fi stories, and when this one started, the music reminded me of Interstellar. I thought here we go, this will be an amazing show, but sadly there were a lot of stuff that was made illogically. Like there was no one who could have consulted NASA or Space X as to how the stuff they were implementing to the story works starting from the rocket that launched them, the spaceship, and overall everything. It should have been much believable if somebody worked on these kind of stuff. Also they shaped the characters illogically, I mean they acted like they weren't thinking a lot of the times.
So I'm a little disappointed, but overall I liked this show, it was a fairly good sci-fi survival horror with a cool twist with Lunar Water. The story was stupid at times (people died when they shouldn't have, and there were no factual science here in anything), but at least the actors were great, and the ending was kind of satisfactory. Not the best, but good enough for one time.

This series doesn't quite hit it out of the park, but, it is DEFINITELY better than average, not just for Korean Sci-Fi, but for ANY Sci Fi. The English dubbed versions I found on free streaming sites were fairly well done, and weren't mis-timed nor did they take you out of the story, which I actually feel in this case was a plus over the subtitled versions I usually prefer. As @movieswatcher stated, the characters were likable (even the villain(s)) in that you could understand their motivations, and not just want to smack the taste out of their mouths. (OK, one dude near the end DID cause me to yell "just pop a cap in this MF'ers face already!" at the screen.) Some of the characters actions were puzzling at times, when there seemed to be another choice that could have been made, especially given the circumstances of a very specific threat they faced. And the big plot "twist" at the end felt quite random, and, while interesting, seemed unnecessary, but, it kinda sorta opened it up for one more go round if Netflix likes the viewing numbers, especially if a particular ability has been passed on to the female lead. (Song-Jaaaan....., you gots some splaining' to do girlfriend...)

As myself and others have stated, ignore the hype-beast, sit back, and watch an very enjoyable series.