I personally really enjoyed this episode, especially the scene where River finally realizes who she's with. It's a pity this really is the last episode we'll see of her (since from her perspective this was the last "night" with the doctor, she only knew of the original faces, and this was her first and only encounter with Capaldi), as I think she was a great character.
I find it interesting that most people on the Internet always seem to have the exact opposite view of most of the Doctor Who episodes that I do. When they hate it, I love it. When I love it, they hate it. It's quite amusing. I mean, the fact that both Rose and Donna are two of the more beloved companions from nuWho is just... wow to me.