I don't think there's ever been a sitcom that has divided opinion so dramatically on BCG.
I've just watched Episode 4 and I thought it was excellent - a huge step up from previous episodes, all of which were pretty decent in my opinion.
As an exercise in dialogue-writing for multiple characters, it was as good as anything I've ever seen either on TV, or in a Hollywood movie or any other kind of film. I may be exaggerating a little but, even if I am, the dialogue was wonderfully written. Very few comedy writers can produce rapidfire, interesting, characterful dialogue like that and keep it up so long.
Based on Episode 4, this is one of the best sitcoms of modern times.
And, as for the performances of the actors, they were once again superb.