Pros:
(1) The location can't be beat if you want to be able to walk to the British Museum, Covent Garden, SoHo, Leister Square, Trafalgar Square, etc. Also, you can take the time directly from Heathrow to the Covent Garden Station, which is a very short walk to the flat. (It's just around the corner.) I should add that it's a quiet street.
(2) The apartment is comfortable and roomy. It is more nicely decorated than many Airbnb flats. Care was taken to paint the walls a nice buttercup yellow and find pictures, bedding and window treatments that look good together. The beds were sturdy and comfortable. The dining/living room is bigger than it looks in the picture. The kitchen is well equipt, including 2 types of coffee makers, a kettle, plenty of pots and pans, etc.
(3) Communication was great. Ann has put together a ver comprehensive binder describing everything in the apartment, right down p where to find spare lightbulbs. We've stayed at several apartments via Airbnb and this really stood out as a best practice, that we haven't experienced previously.
(4) Our flights were delayed twice, but Ann's partner was able to adjust her schedule to meet us when we finally arrived, which was ver much appreciated!
Cons: none!