It was pretty funny. Danny McBride is such an asshole. Super funny cameo the next time you see him. This movie had a lot of CGI which I don't think they really needed. And like a lot of Apathow-influenced movies there's too much penises. This movie is actually at 81% on Rotten Tomatoes and certified fresh.
I went into this expecting something like Hot Tub Time Machine or The Hangover. What I got was lots of penises and drug glorification. It had it's funny moments, and I don't regret seeing it, but if I had to sum it up in a word, that word would be: Gross.
Oh yeah, my enjoyment of the movie also was hampered by having no idea who Danny McBride was, and only knowing Jay Baruchel as one of the supporting actors in Knocked Up. There were a lot of jokes about their respective careers and/or personalities that just meant nothing to me.
I suspect the only thing that will stop the Simpsons is if one of the main cast (or Hank Azaria or Harry Shearer) dies or retires. And maybe not even then. And it will still be on in syndication by the time *I* croak.