A bit of a letdown. The funny thing is, I complain when I'm left hanging in a series finale, and now I'm complaining because the loose ends have all been tied up! Somehow Zach holding a gun on Susan and Mike isn't much of a cliffhanger, since we KNOW that they're not going to die because they're the main characters!
I doubted that Rex was really dead. That was actually the most intriguing part of the episode.