After one listen broken up over about 6 car rides over two days:
Cons:
Not nearly enough metal. Like, 2 songs total, and one of them was too short and had no solo. This album is extremely far from being metal.
Not enough technical chops. A few total sections. The only demonstration of prog on this album is the frequent time signature changes.
Relatively boring rhythm work relative to the best DT. Don't need insane riffs every song, but I need them sometimes.
Drum machine drums. Additionally, Mangini wrote extremely safe drums. I can recall exactly one creative drum part, and it lasted about 5-10 seconds. These are really two seaparate negatives.
Many songs were brutally underdeveloped, and many others were totally unnecessary.
Too many piano, soft, "emotional" songs. I would say all but 5 or so of the actual songs fall into this category.
Myung is underused, but I don't really care admittedly.
Not enough guitar soloing.
Pros:
Awesome vocals. Seriously. I have zero complaints about them.
Beautiful, rich orchestrations and instrumentality. I would even call it astonishing.
Petrucci has become a better soloist. His average phrasing has improved. I really dug some of the solos on here. Were they his best ever? Well, unfortunately things like Under a Glass Moon and As I Am exist, so no, but the average quality is higher than usual. Too bad there weren't enough solos...
No corny Rudess keyboard solos. I can only remember 2 solos from him, and both were at least decent.
Great, clever concept and story.
Lots of great audience moments for live performances.
Favorite Song At the Moment: Moment of Betrayal
I am sure every single one of the opinions I posted above will change. Album pales in comparison to Underworld, IMO. Sadly, I expect Circus Maximus to put out an extremely poor release as well based on the 2 songs I have heard from them, so it's gonna be until SX comes out again when I get a new top notch disc.
Overall rating (so far): 6/10
DT albums I like better: Scenes, Systematic Chaos, Black Clouds, ADToE. Astonishing is probably better than all the other ones, IMO.