I'm not even far into the game - hell I just finished "Hushed Whispers" and I must say, that it completely blown me away.
This quest is crazy good - the events, the writing, the boss battle...and it's ending. It was very innovative and really, really interesting.
A real quality, especially compared to quite linear* and predictable quests in DA2 and even DA:O. During the entire mission I really wasn't sure what's waiting behind the corner. If more main quests are as good as this... count me in.
*By linear I mean here that it was a straight, predictable path from A to B, where most of the time you knew what to expect.
I cannot wait for the next playthrough, because I'm interested in how the Templar alternative looks like.