I spend one month is Richard's house, and the overall experience was really good. The room is small but very nice and with a big closet that has space for luggages. Richard provided me with clean bed-linen and towels. He is a perfect host, he's always ready to answer question and he is also very helpful.
He menage to solve a nasty situation due to other guests' bad manners in a brilliant way, and he never stop apologizing even if it was not his fault.
I strongly recommend to take a room in his house, in particular if you are staying in London for long period (go for one of the larger rooms), the location is really convenient and you can find lot of buses in the area.