We stayed with Marcus and Joanna in October 2013 for 3 nights. The house is fabulous, the room and (private!) bathroom are excellent and thoughtfully put together (thanks for the bottles of Evian!).
The location is second to none - step out onto Portobello Rd - markets, cafes, restaurants galore. Easy transport to the rest of London. Read the house guide Marcus and Joanna put together - it has good eating recommendations. Highly recommend this lovely, easy going couple and their wonderful home.