What a cool concept and use of genre! Was impressively engaging considering the characters never left the office. Nicely edited /sound-mixed with the phone calls and things as well, and was well acted - loved the main character and the way they made her "too nice" (i.e. too thoughtful).
Comedy was a little hit-and-miss and I prefer films that aren't all in one location if they don't have to be (personal preference though I suppose). I also was just left wanting more by the end... I suppose that's a good thing in a way though!