A lot of very positive comments have already posted - which I thoroughly agree with. Ann has been very responsive and quick to communicate which made both check-in/check-out and related questions very stress- and hassle-free. The neighborhood is great (Sainsbury's within walking distance, several cozy and reasonably-priced restaurants just around the corner) and we very much enjoyed the proximity to the British Museum, Covent Garden and the West End. Overall a great experience!
One very small thing to note: Holborn tube station is closed for outbound trafffic (i.e. leaving from Holborn) during the hours of 730am to 10am (escalator maintenance) til mid-2018, so for the early birds I would recommend booking Uber or walking to Russel Square (another station within walking distance).