I just watched Unification
This episode is at once both awesome and disappointing. Good character stuff, with the idea going in that sweeping change was about to happen. Instead we get something akin to a Scooby-Doo plat, and in the end, things wound up back the way they were. Tat aside , I loved the episode. It actually serves as an almost essential prequel to the 2009 film, explaining why Spock was involved at all as to what happened to Romulus.