I saw it but it was slightly confusing. I might have to watch it again to understand the plot. I didn't get it at all.
But it was really really good. In the end, it was so confusing because of the "Dream within a dream" 4 times. I was like hella confused by that, you can't dream that much into a deep sleep and not wake up until 4 times later. But when they did that scene, I didn't get their plot. Why did they need to get to the door so badly?
That's all I'm saying, I don't want to ruin it. The only plot I got out of it was Leonardo's past and how it ties in with his memories, is that the plot? Let me know if I'm hot or cold...
Although I didn't get what this movie is about 
I love movies that make you really think after they're over.