I also agree with GazL.
Some episodes just take things to far, like the episode about Mr Garrisons super fast machine to replace plains, and also the one that all about the adventure of a hamster up a guys arse, that was repulsive. Some are stupid too like the one about how the us government are blamed for everything (specifically 9/11 attacks) just to make the world think they're capable of doing such things.
And then there's the imagination land episodes, they went on for ever and board the crap out of me.
Other than all that though, i love south park.