SPOILER ALERT: this post contains references to the ending of the film.
Its protagonist, Aron Ralston, could well have been turned into a sickly sweet caricature, but Boyle's deft use of his hallucinations, memory, premonitions, or whatever you want to call them, are handled in a way that firmly grounds him in the reality of his circumstance. The film doesn't try to pretend that Aron never gave up hope, and it is his constant prevarications between hopelessness and persistence at the only option available to him that makes him both real and truly inspirational.
There have been some ridiculous stories about people finding the blood and gore too much. My suspicion is that these folk must have been completely shielded from any exposure to blood in their entire existence to be so extremely squeamish. There is nothing particularly extreme about the depiction of the removal of Aron's forearm, you might just need a strong armrest to grab hold of at a few critical moments. Limelight Cinemas' hardware held up fine!