It's a nice twist that you have no idea upfront what or who you're facing, and the moment the targets are revealed yielded surprise most of the time.
What leaves a bitter aftertaste IMO though is the ending screen that says you "correctly" guessed which one, in my eyes, to kill without motivation. There's no backstory as to why I have to shoot one of them, why it's "right" to kill one but not the other. The peaceful music and the setting inside a house with a nice view only adds to my disturbance . That can IMO be a plus if you want to confront the player with their own moral failures or address some event in history, for example, but without context it just doesn't work for me.