Definitely worth watching - I fell in love with it by episode 5 - the first 4 for me weren't that great - but was necessary to see the character development later on :)
ah, I'm so glad my internet is back up so I can watch this drama - I had been thinking about this drama the MOST during the 2 and a half weeks that my internet was out - I love it so much!!!!!
I skipped alot during this drama from episode 29ish to 98 - then i stopped skipping lol - i'm only interested in Muyeong and Jisu's scenes and now Sanghyeon and Eunju again...no one else really interests me - i'm on ep.130 now...
ep.77 @18:20 - F.T Island singing?
ep.89 @27:46 - sorry sorry by SUJU lol
ep.38 - last episode Chowon is on :D
ep.5 - the episode Chowon comes on >_<
ep.1-19 Suin's hair makes her look really ugly and makes her nose and mouth look really big...
ep.20-22 Suin changes her hairstyle and color and she actually looks really pretty now..
ep.87 @19:38 - place from You're All Surrounded?
ep.46 - Seongtae gives me the creeps & he comes on screen....
you'd probably like Sirius - it's 4 episodes and wasn't boring at all for me - you have to watch into the credits though too as they show a scene that I believe is somewhere in the future ;)
Dramas that I don't think are boring: Crime Squad, Fugitive Plan B, Ghost, Who Are You? (2013), God's Gift, My Girl, Witch's Romance, Smile Dong Hae & Smile You if you can handle long dramas..., The Devil, Two Weeks, & Man from the stars? - lol, most of them are detective like dramas (except the long ones)...
Triangle got good by episode 5, Hotel King got good by episode 7, Glorious Days is really good - these are airing dramas....
Completed dramas - what genre are you looking for? any?
FYI - I happen to be watching Flower Grandpa Investigation Unit too - yes it's good - but it's on a comedy level - not to be matched with the seriousness of this drama. Nothing about GD is boring - and if you REALLY thought it was boring - you wouldn't still be watching it.
News 
ep.89 @27:46 - sorry sorry by SUJU lol
ep.38 - last episode Chowon is on :D
ep.5 - the episode Chowon comes on >_<
ep.1-19 Suin's hair makes her look really ugly and makes her nose and mouth look really big...
ep.20-22 Suin changes her hairstyle and color and she actually looks really pretty now..
ep.87 @19:38 - place from You're All Surrounded?
ep.46 - Seongtae gives me the creeps & he comes on screen....
Dramas that I don't think are boring: Crime Squad, Fugitive Plan B, Ghost, Who Are You? (2013), God's Gift, My Girl, Witch's Romance, Smile Dong Hae & Smile You if you can handle long dramas..., The Devil, Two Weeks, & Man from the stars? - lol, most of them are detective like dramas (except the long ones)...
Completed dramas - what genre are you looking for? any?