We had a lovely stay at the annex. Very clean and well equipped. If we needed anything, Joanna was very responsive. Also, the breakfast provided was perfect. Very nice hosts who will make sure that you have an excellent stay.
The annex is in a nice neighbourhood, close to the Putney train station and to the tube (East Putney). Very convenient to go to Westminster (on the same line). Also, many buses can take you to South Kensington.
We highly recommend this place to anyone, we loved our stay.