The apartment is very spacious, which is unusual for London (or any large city) and the location is excellent. The neighborhood is great, with lots of restaurants and four groceries. It is also close to the train station.
The apartment is in an older building, and thus may have some issues related to that. For example, we were asked to refrain from using one bathroom on the fourth day of our stay because, apparently, the plumbing was leaking into the apartment below. We, of course complied, and managed to get everyone through the other bathroom in time to catch our plane the next day.
That said, the apartment is large and comfortable, and I recommend it to travelers.