Initially I enjoyed this show a lot and looked forward to it weekly. As it has gone on the raunchy humor for the sake of being "edgy" has started to wear thin, but then there tends to be an episode that reminds me why I love it.
I'm not sure that it's fair to have to rate all of these seasons as one show. I loved the first season, enjoyed the second season, never finished the third season, and so far am not disappointed with the fourth.