I watched and, of course, the aftermath of the heavy drinking session was gross and, as another poster said, stomach churning. However, I think it was completely necessary to show how completely out of control Joseph's life is and how his utter degradation gives him the impetus to go to Ireland.
Having watched the second episode, I think it is absolutely brilliant. Stephen Graham's acting is so natural, convincing and moving, as is the acting of the rest of the cast. (I do agree that some of the dialogue is difficult to hear though).