I love the tone and pacing to this movie and once again, Shane Carruth wrote, directed and acted the hell out of this movie. Excellent job on casting the patients as well.
The only thing I found a little distracting was the beard that Carruth has makes him look like a cross between Tom Yorke from Radiohead, and the kid who played Eric's best friend, Jason, from Boy Meets World. Other than that, it was a better than solid psychological thriller that keeps moving tastefully with performance executions that really make you care about the characters. Definitely would recommend it. And if you haven't seen his first film, Primer, do yourself a favor and watch it.