This is one of these small hidden gems I sometimes stumble upon. The storyline might not be unique or new, but the execution of the story is great. It is kept lighthearted and funny.
Character wise we get this Emperor that is somewhat cold and indifferent towards his Empress who is a bit of a troublemaker especially in regards to the managing of the harem where the Emperor's favorite concubine rules. When the Emperor and Empress switch bodies they have to rely on each other to get through their everyday life and the Court affairs.
Acting wise this is pretty good. It takes some skill to portray (believably) a character of the opposite gender and the main actors possess that. There is also development of the main characters which is good, given the limited timeframe.
So, if you love a good body-swap comedy, with lots of funny moments, this is definitely well worth watching.