I had 8nights at Liz's studio, it was my first time in London, but I found it easily with the given directions. It was in an ideal location, close to the tube, 10mins walk to Hampstead Heath, cafes, pubs, shops etc and a quick tube trip to the city.
The studio whilst it isn't large is a very comfortable, light and airy unit and had everything I needed.
Liz is a great host, unobtrusive, but available when you need her, I would be more than happy to stay at Liz's studio anytime I was in London.