We enjoyed our time staying at Diana's place in London.
The location is really great. Close to the underground station Russell Square (5 minutes walk)
Because I was traveling with my family I didn't want to use underground when we had our luggage with us, so the location is very important.
The St Pancras train station is within a 15-20 mins walk distance which you can take train directly to Gatwick Airport.
The only thing that bothered me was the stairs because we all had large suitcases with us. But it was easier to carried them down, so don't a very bit problem.
Overall, it was an excellent choice; especially in London where hotels in such locations can be very expensive.