We had a nice stay, the flat was easy to find, the appartment was as described by Robert and the pictures.
Unfortunatly we didn't meet Robert in person (he was on holidays) but he told us all we need to know by mail and all the process to get the keys and go to the appartment, he also gave us a list of place/restaurant to go.
The flat was clean, equiped kitchen all we needed.
And the underground is at 10 mins by walk (two choices Kennington Station or Elephant & Castle)
Robert was also very quick to answer at our questions, we really enjoyed our stay, we would stay here again if we come back to London.