Didn't like it. The events were boring and uninteresting, they also felt very fake, very convoluted because they left no room for errors, otherwise if the mane6 failed at getting their cutie marks then the show would have went all dark and bitter like the fanfictions which this episode spawned.
The execution of telling the stories: make the cutie mark crusaders go ask the main characters] is a bad idea for structure and time management. Weird that they didn't just break the wall and made a special episode where the mane6 fillies interact with one another.
It made me ask for a 2parter and it raised more questions than it answered.
And the ending with Rainbow Dash fixing everything felt like Scootaloo's fanfiction.