This... was definitely one of the most 'intricate' of sci-fi movies I've seen. There manages to be everything from interesting takes on the future, good action, clear character development, comedy and emotion, and a bit more. There are some parts that are more than intense and the kind of things that don't normally make it out of novel form and onto the big screen. I will say that as visceral as they are, those scenes do advance the movie so they aren't pointless. A bit confusing in areas as well, though for the most part it all gets cleared up.
The things that are 'different' in the film seem to be worthwhile and help it to stand apart as its own creature. I also loved that the previews give away almost nothing of the film; you will know more than a basic framework for the premise, but you won't know what's coming next until it happens mostly. Glad someone in Hollywood finally figured out that people don't want to see the whole movie in the trailer.
Like all time travel films you will have to suspend disbelief a bit, though that's easy enough to endure. If you like to think during a movie you'll likely enjoy this.