Stephen Dorff and Lili Taylor and Jared Harris are all great in this film, particularly Dorff. But the film's biggest weakness is that everyone in the movie is so weird you don't really care what happens to them. Only Dorff manages to invest his character with enough humanity and vulnerability that you are actually interested to learn of his ultimate fate. I was kind of surprised to learn that Solanis is held up as some kind of proto-feminist lesbian guru when it is obvious she's only twisted and insane.
Imagine if the situation were reversed and Solanis was a man calling for the cutting up of all women and denouncing women as an inferior race. Such a viewpoint would be considered monstrous! Solanis is a crank and a fool, so it's impossible to take her character's world view any more seriously than the guy down by the subway station who mumbles to people who aren't there.
The entire Factory scene is rightly exposed as the pretentious, ridiculous collection of sub-mediocre talent it was. So the viewer isn't surprised when Solanis shoots Warhol, as he couldn't say no to anyone around him and surrounded himself with so many weirdos it was inevitable.
Would this film have been lauded had it been a biopic of Mark David Chapman? I don't see much difference between Solanis and Chapman frankly...both complete, colossal failures in life who managed to gain notierity through murder or attempted murder.
In summary, this was a well-executed take on a rather idiotic topic. I'd rather see the director use her talents to make a movie about people who deserve the effort. Not worthless no-talents like Warhol and Solanis.