I personally think the author has a great drawing style, I think he's a great artist and I like the sketchy feel we get in some chapters.
although the picture above with mikasa, I like it and I know she is really toned so she can maneuver with the 3d tech, but I feel her stomach is a little too flat, but its not that big of a complaint, the rest is fantastic though, especially the arms.
I love the art in this manga, it gives it a really unique feel.