This episode was fantastic. The animation was really good (except when there were profile shots, especially during the first half, but what else is new?) throughout, the scene where the girls show off their high school uniforms was HILARIOUS, and there was just a lot of great music and emotion throughout.
I love that they reused the Haruka/Michiru ending. I love that they used the theme song during the "battle" scene.
Overall this season was a HUGE step up from one and two, and I personally enjoyed it more than S. HOWEVER, there is still a lot of room for improvement. If they hadn't wasted so much time every episode repeating the last 3 minutes of the previous episode, if they hadn't wasted so much time on showing stock footage attacks twice in some episodes, or on showing all the stock footage attacks in basically every episode (especially in the same order and to the same effect), and if they had held off on the ~Dream arc preview~ stuff, there would have been an extra episode's worth of screentime that they could have devoted to developing Haruka and Michiru's characters and relationship (to say nothing of other characters). I'm really mad (though not surprised) that they kept Haruka's assault on Usagi but never gave us a single HaruMichi kiss. (Nor did they really explain why Haruka kissed Usagi nor showed how Michiru felt about it...or anything, really. Poor Michiru. Poor giant-mouthed Michiru. Seriously, girl really could have used some lipstick/a smaller mouth. Her design was just...inelegant.) We could have also used more time developing Hotaru and Chibi Usa's friendship. They started off good but then...it's like they forgot about them for a few episodes, which made the sudden ~soulmate~ stuff at the end feel a bit abrupt and unearned. It also would have been nice to have actually seen the girls studying for their high school entrance exams (and Mamoru preparing for university).
tl;dr: My biggest complaint with this season was its gross time mismanagement which led to some character under-development
Still, as I said, a HUGE step up from seasons one and two. The animation was better overall (though, again, could have definitely been better), as was the writing. There was a lot of solid, genuine humor (especially in this episode) and character development. The Inners had more personality and were more useful this time around (although they kind of went away a bit in the last two or three episodes).
Season III has made me hopeful for Crystal's future. Bring on the Dream arc. Let's hope they continue to improve.