I started watching this show (had seen 4 episodes) and was almost ready to give up on it after Playtest (which I thought how the episode was done was just incredibly stupid).
However I watched San Junipero last night and I have to say that the episode is one of my favorite of any tv show OAT. I'm a big fan of Mackenzie Davis from Halt and Catch Fire. Mackenzie and Gugu Mbatha-Raw are phenomenal in the episode. Also Gugu looks breathtakingly beautiful as well imho.
If you're on the fence whether you want to continue watching Black Mirror or not just tune into San Junipero.