Sam Raimi's best movie? Hard to say. What I would call his three best (this one, Evil Dead 2, Spider-Man 2) are all great for very different reasons. A Simple Plan is, for my money, an all-time klassik thriller... one of the few movies that genuinely gets my stomach in knots at a few points, but also with uncommonly strong character work. The morality of the film I particularly like. We've seen a lot of films where good people do bad things to get money, but rarely are the movies this good at expressing their thoughts and beliefs in a way that people might do in real life. For me, it's kind of like Unforgiven, where a lot of seemingly simple and straightforward dialogue contains a lot of truth and insight.