The drama delivers a great story of brotherhood and politics. It's not a very emotional drama, so maybe you will not cry watching this, but it delivers a great message of friendship, sacrifice for greater good, and idealism.
IMHO, because the drama is loosely based on real history (which they turned into a fiction), you don't see much of character development, but more into how the characters from two factions use tactics to fight one another. Not much character development means that the personality and the ideas of every character in the beginning stays the same until the final episode (except for the Empress'!).
Some people got disappointed on the ending, but I'm rather satisfied as it shows how the main character's heart and priority never changes. From the very beginning he knows that peace is the most important thing, and peace does not lie only in one family name. His determination and personality never changes until the very end.

I love how Regina Wan played the empress role. Very elegant, especially the way she speaks.

I also love the opening and ending music. Perfectly matches the drama.

To sum up, the series is worth watching if you're not looking for a too emotional drama, or wanting a good politics drama.