I think that the better is to see the original 50-episodes drama, the storyline is better explained and the story is complete. These 20-episodes short drama is nice but many important details are missing, also there is no new scenes or content in it.
So, if you have seen the original long drama, there is no necessity at all to see this one, if you haven't and don't want to see a 50 episodes long drama, you can watch this redux but I suggest you to see the 50-episodes drama.

Anyway, the story, casting, and male carachters are awsome.