I've just seen this.
I enjoyed it - I had never seen any trailer or commercial so it worked for me. I was bought into Noyce's and Dr. Solano's conspiracy theories so the idea he could be the patient didn't even touch me
It is one of those movies where you can collect so many hints and details when you think back at them. Cigarettes, water, the band aid on his forehead etc.
(One open question for me is: was the scene in the cave with Dr. Solando real?)
Re: the sane vs insane debate, I do think he was crazy.
I don't believe the screenwriters/director meant to make anyone think that he could be sane, BUT did they mean to leave us with the doubt that the shrinks were actually bad and did this huge role-play just as a sick experiment and not as an actual therapy?