The Mervyn's place was great as well as the host himself. Everything went smoothly.
The location is great for people who love to live next to the center (you can take one of the direct buses or a little walk to the tube) and get all the benefits from local environment (nice markets on Sunday are in a 10-minute walk as well as pubs or cafes of any kind).
The flat is very nice, and you can use the kitchen, the living room, and even the balcony when there's nice weather. The room is clean and pretty cozy. It was warm, too. The bathroom is in the room (behind the door, of course) and it's good (a bit chilly sometimes though because of winter).
A nice choice for staying. Could be one of the best options for the money.