There are movies out already with the "I did this big thing" theme, so it's refreshing that this is not another. I think the trailer clips I've seen point that out fairly well.
But watching the clips, I still get the feeling it isn't quite real: Her pack is huge, but it just isn't that heavy, not the way she handles it. And another, the Kennedy Meadows trailer: Coming off the trail, she AND her gear just look way too clean.
But I still want to see the movie. It sounds like a good story, set in a hiking environment. Hope it shows in my area.