Watched the movie, loved it. Lets the viewers decide if it is real or whether it is all simulation theory and throws breadcrumbs along the way. Honestly isn't that hard to work out what's going on and unfolds the story in an elegant way so you can't really tell what is real and what isn't. It's a sci-fi drama that delivers. Don't expect big explosions or dazzling graphics, so if you love action movies you probably won't like this movie. It's nowhere near as complicated as Primer but I'm reading similar reviews where people don't like it because they don't understand what's going on. Just put down the phone and watch it without distractions and it's really not that hard to follow the story. There are subtle hints throughout the movie (just like Primer) so if you aren't playing attention you probably will miss a lot of information. If you like sci-fi and like the idea of simulation theory then this is a cracker of a movie to watch.
*spoiler*
And yes you don't know if he's in the simulation or just a drug addict. If you look at it from a drug addict perspective it's quite sad and moving to see his decline and you really get a glimpse into his drug induced state of mind, but if you look at it from simulation theory he chose to be stuck in the simulation with his daughter that isn't real away from his partner who got back to a blissful utopia until he dies and (maybe) ejects from the simulation. It's the duality of the two that I find intriguing, and after all how do you really know you aren't stuck in a simulation? What does it mean to be "real" anyway?