Watching this recently made me appreciate it a lot more and Time-Flight a little less.  For the Faceless Ones, this was a very creative setting for a Doctor Who story.  It's full of great moments of dark atmosphere and I enjoyed some of the character work of the terminal staff as they grapple with the increasingly disturbing situation around them.  This is not however, a great story for Ben and Polly's exit.  Neither character really shines much and Jamie in comparison already feels much more clearly at home with the adventuring.  Jamie's got some fun moments in this one and definitely helps make this story a lot better than it might look on paper.