I like good music, and sometimes a concept album has good music.
I feel SFAM has some good music, but much less good music than other DT albums, hence, I don't like it as much as others; it's mainly the ballads that kill it, subjectively, in my opinion, of course. Too many ballads and not enough prog metal, and I don't like its ballads. Now, Awake, its ballads are top 10 material, right there.
The story, I could care less, really, it didn't seem to play much of a role in the grand scheme of things, and honestly, if I want a good story, I'll go to the bookstore and buy me some sci-fi and fantasy. Plus, I don't see any sort of connection to Metro 1, besides name and some musical elements.