It is hard to choose the best episode from season 6, i like all episodes there and there is no episode which I would call as bad (even some episodes which are considered to be weaker as Shadow Play or Sight Unseen), but I agree that this is the best episode of the season. And in terms of Jonas, I also think that this is his best episode. I also liked him very much, I was dissapointed that he was forgotten so soon. Maybe I should not say it as it is not the much popular opinion but I liked Jonas much more than Daniel and I was quite dissapointed that Daniel's return accompanied the departure of Jonas.