I stayed with Ed & Catherine for three weeks as I was on a research visit in London. The apartment was really nice and Ed & Cathering are very welcoming, easygoing and lovey people. They kind of adopted me during my stay as we sometimes made dinner together, watch TV together, had very nice and interesting talks, had brunch and they even invited me to one of their parties (they have very nice friends too). At the end, I felt more like a roommate and a friend than a house guest.
Moreover, Brixton is a really lively and nice part of London that I had not explored before. It is very well connected to public transport, with many buses and the Victoria underground line. Brockwell Park, right outside their apartment, is one of my new favorite spots in London.
So, in short, I can really recommend staying with them, I will certainly do so when I return to London!