Had a good stay at Keith's. Room I stayed in wasn't the one shown in the listing but looked very similar - found it clean and nicely prepared, if not somewhat minimalistic. Apartment is spacious and conveniently equipped with two bathrooms. Living room and look kitchen are used regularly by the family hence are not super tidy, but still acceptable (kitchen could be kept more clean though).
Keith is a welcoming and responsive host - waited for me upon check-in at midnight, and even met me in the street and helped with luggage.
Location is great thanks to Camden's amenities and fantastic public transport connections, yet also residential and slightly away from the neighborhood buzz (railway just across the apartment though, and trains can be heard whole day).
All in all, Keith's place is good value for money for a short-stay in London if making limited use of common areas. Recommended!