Heavy Rain was pretty good, although I felt betrayed at the end when a single failed button-press ended a character's life.
I had gone to a lot of effort to make sure that character had all the right clues and was in the right position to make this a happy ending.
It has its flaws though. Despite its immense range of options, there's not a whole lot of replay value because there's no much gameplay to speak of it. The entire game is quick-time events. There only appears to be one "correct" path, so if you play well the first time through, then the only way to experience everything else is to mess up.
A brilliant narrative experience - once. But for a game, there's not much game. If I were you, I'd rent it and play the shit out of it over a weekend, in which time you can safely complete it for a fraction of the cost.