Oh yes, DA:I is excellent so far. I read somewhere that they estimate about 150 hours of play, if you do all of the side quests. I believe the first two games kept me going for about 50 hours each (Steam says 90-something for DA:O, but that also includes the Awakening expansion).
I've put just about 50 hours into DA:I so far, and I think it's believable that I'm about a third of the way through. And it's not dragging. Not at all.
One piece of advice though, if you do pick this one up. You should try to unlearn what Bioware has taught you to do in the earlier games in the series, and with Mass Effect. That is, they previously trained us all to complete a zone before moving on, and to generally do as many side-quests as you can before advancing the story. Both of these are mistakes to do in DA:I, which is much more free-form, and clearly is meant for you to fluidly go in and out of the zones over time.
The zones are HUGE compared to previous titles. And the first one they put you in, The Hinterlands, is probably one of the largest. You can spend 15 hours in that one area alone, and if you try to do it all in one go, you'll wonder why the game is dragging and the story isn't moving forward. It's better to advance the story, until the "recommended level range" for the story missions holds you back.
There's so much depth and complexity in this one, it's quite amazing. And yet, they kept some of the streamlining from DA2, in a successful blend.
