Takes place near the start of the 80s, romance included, has similar feeling (note that I have watched up to episode 2 so far)
I am in love with vintage feels and styles.

Both have the same male main lead and genre. Cops vs culprit is a huge theme as well. Great action scenes.

Same writer and similar scenarios
Lee Jong Suk is also in it.
Instead of having dreams Lee Jong Suk can hear people's inner thoughts.
There is also a strong focus on the justice system.

Multiple Personality Disorder, Cringe behavoir, back and forth, romance

M is a older Korean drama which has more of a soap opera feel to it but it's worth the 10
40 min episodes.

THE SUSPENSE IS AMAZING

Both center around show production and have a idol cast member (Siwon). While Producers centers around variety. The King Of Dramas centers around the production of drama and the relationship between cast members, writers, producers and ratings.