I watched this special on KBS on 15/5/2018 and I have to say I liked it better than I expected. Still a bit boring and kind of pointlessly melodramatic (which seems to be a trend with KBS drama specials...) but while the story started super cheesy I appreciated that it slowly became more and more realistic.
I've recently seen Chae Soo Bin in I'm Not a Robot and I really enjoyed her performance here as well, she is a joy to watch!