My partner and I stayed at Natasha and Ed's place for two nights. I would highly recommend staying with them. The house is lovely, and the room, like the rest of the place, was spotlessly clean and very comfortable. The location is convenient - Brixton is the Southern end stop of the Victoria line and thus easy to get to, and it's a very interesting part of London. The flat is a ten minute walk from the tube station, or you can take a bus.
We met Natasha when we arrived and had a tea and nice chat with her, and she and Ed left a lovely breakfast for us in the kitchen on both mornings. That blueberry-apple jam that the other reviewer mentioned? It's delicious :)