I thought it was very well done, especially considering the glut of super hero movies with no real substance. This one makes you think, and it stays with you after you leave the theater.
Lots of small touches in the sets and scenery that, if you're a boomer, you'll recognize. Good screenplay and music too.
Phoenix does a great job in the lead role. Both physically and emotionally he brought his whole game to this project. Deniro seemed to me to have called this one in, but that's been the case for 90% of his stuff for the last ten years.
The movie's not what I would consider "entertainment" in the conventional sense, but I think it's a pretty good study of how a shooter might develop. Worth the 10 bucks.