I booked the Imperial through a travel site based on location. Russell Square is very convenient to the British Museum and not far from King's Cross / St. Pancras stations. A tube stop is near the hotel. A very nice small park is immediately across the street.
My single room was just that: a room just large enough to hold a single bed, with a small desk and a not very comfortable (and somewhat shabby) chair. ONE quite thin towel was provided each day.
London is an expensive city, but I've definitely gotten better value that the Imperial offered.