NWN2: Mask of the Betrayer - Review @ GameSpot

GameSpot's review of Mask of the Betrayer criticises the spirit-eating mechanism and camera but praises the choices and puzzles, calling the expansion "mature".  The score is 8/10 and here's a snip:

The expansion also does a great job of diversifying the gameplay. In NWN2, there was almost no situation that couldn't be solved with a little combat. On the other hand, Mask of the Betrayer is packed with all sorts of devious puzzles. For instance, a trip to a wizard school will have you trying to figure out an elaborate mirror puzzle, as well as attempting to break a contract with a devil. This is an expansion that will make you think, and that's a good thing.