Great location, very clean and modern apartment, easy check in, wi-fi always worked. Just a five minute walk to Victoria Station, from which you can get to the Westminster sights in just a couple of stops. Fifteen minute taxi ride from Paddington, where the Heathrow Express arrives. Coffee across the street, good Italian food downstairs, a full Sainsburys grocery store a block away, and traditional pubs less than a block away. Taxis come by frequently if you want to travel that way. Note that the neighborhood is busy--restaurants, stores--which means that there is traffic and sidewalk noise until late at night. But it always felt safe.
The place is small--though there are bed spaces for four, we had three people, and that really is the maximum you can comfortably fit without stepping on each other.