We watched it last night. Confusing beginning and a little slow. I almost lost interest.

 What a great movie!! We will be sure to see it a second time. It's one of those movies that will be even more enjoyable the second time around. Your brain is trying so hard to wrap around the concept and the details the fist time, you miss a lot. The only difference is that I wish there had been a different male lead. I'm not a huge Leonardo DiCaprio fan, but he did a decent job. Matt Damon would have been a better "fit", imo.