I just saw this movie two days ago. While parts of it were kinda lude, it did seem true to life for a bunch of meth heads. Even the part with the shit. C'mon anyone who's done a lot of drugs can relate, even laugh about it.
Other parts of it were fucked up. NOt going to spoil it by saying what. All in all it was worth my four bucks to rent it and I would suggest others rent it if they enjoy watching movies about drugs. Just be careful who you watch it with though.