Wow.
This movie was perfect in almost every way.
Sure, the subject matter may not be for everyone, and therefore someone wouldn't think this movie was all that great, or even good perhaps. But if you can objectively look at a movie for its component parts and how they lead one into another, setting up everything that happens in a logical and consistent manner, you would have to admit that this movie does exactly what it sets out to do. The progression of events is internally consistent without completely giving away every plot beat. Including the ending. And if you actually like this subject matter, it's a no-brainer that you should watch this movie.
I also appreciate that the entire movie was only 70 minutes long, because it didn't need to be padded with fluff. Now, I wouldn't complain at all if someone threw a little money at it and put some CGI battle scenes into it to make it another 10'ish minutes, but it would add literally nothing to the movie beyond the glitz factor.
The main actor was amazing, and since he is pretty much the entire movie, that's certainly fortunate. He conveyed every emotion that we needed to see, usually without speaking, and he fit the part (physically) that he was playing perfectly.
I could go on, but basically this movie blew me the fuck away. Easily 9.5/10. I'm trying to think of something to explain why I took a half point off, but I can't, so fuck it...10/10!!!