Close enough to the center of London that I watched New Year's Eve fireworks from the dining table, but still a fairly peaceful neighborhood. There's a bus stop out front, which will get you quickly to shopping or transit centers. The building is very quiet; I never heard neighbors or street noise, other than the occasional police siren. The apartment is absolutely gorgeous and clean with great views of the city.
I only had 2 issues with my stay. The housekeeper forgot to leave towels out, so I bought some nearby. The concierge desk is staffed '24/7' but the only 2 times I needed them (check-in and check-out), they were gone. The only way to reach them is by phone; no buzzer or monitoring of the lobby CCTV. My last day there I asked the new concierge (literally his first day) if there was anywhere to put outgoing mail and if he could arrange a taxi to Heathrow for the next morning; he couldn't help with either.
Clotilde is a great host; I would definitely love to stay there again!