From what I've heard of them, As I Lay Dying aren't terrible bad, ocassionally the lash out a nice melody to counter the generally heavier rougher side which seems to work, the vocals could do with being somewhat cleaner, but they're still young.
It seems to that most of the metal you're going to find coming out of the US at the moment tends to be either Metalcore or have least some hardcore influence. It's not a problem for me because I like some hardcore, however Metalcore tends to be a genre a I generally stay away from.
So, As I Lay Dying and Throwdown (I didn't used to like them but they're growing on me) but on the otherhand there is the likes of Hatebreed who aren't awful but are really just rehashing what Slayer did 20 years ago, albeit not as well, and considering my opinion of Slayer that's very difficult.
Nile are good, but they've been around a while and lets face it as much as I respect the brutality of their music and the fact that they seem to not give a fuck that people don't like it, they do become terribly boring after a while. Although for me, that assesment applies to just about every pure death metal band.