if i had come here right after watching, i would have given 10/10 for all regardless of the ratings.  but i went and watched the Chinese version and had to deduct some points here, because the original was so good. I understand the criticism this one got.
anyway not here to review about the Chinese version but the korean version. first of all i have to say, i loved this drama...  i had stopped watching kdramas for almost seven years because it got so monotonous and boring, then came across this with no recommendation and no expectations  i didn't even  read the synopsis,  and then wow just wow,  the story got me hooked. coming to the second point,  the cast...  They were all pretty :)  and then there's lee junki my all time favorite.  but kang ha neul caught my eyes  i loved him as wang wook, 8th prince.  and iu  i guess she did Ok
Lee junki was a standout though.
thirdly, the music  the soundtracks...  well some of them had English words and rap,  which kind of didn't fit the historical settings  but damn they are all so good,  the soundtracks was one of the best I have to say.  

and lastly i couldn't get over this drama for weeks.  it left me shattered, normally I don't watch tragedy  but this drama is worth it.  worth all the tears and emotions u are going to invest.