We had an amazing stay! We were a party of 6 (2 moms, 4 kids ages 18-21) and the place worked out perfectly. The location is central to everything. You can walk many places and are a 10 minute walk or less to a few different Tube stations, providing ready access to many lines (Leicester Square, Tottenham Court, Covent Garden, Piccadilly). The immediate neighborhood is full of restaurants and cafes, so food is never a problem.
The flat itself is amazing! Large and spacious with 2 full baths, it accommodated our party well. It was a heat wave while we were there and while not air conditioned, the many windows and doors provided plenty of cross-wind breeze to keep the living space pleasant. Each bedroom had a stand fan, which also made sleeping more comfortable. We enjoyed having our morning coffee and our evening cocktails on the covered porches.
Other reviews have mentioned inconveniences with appliances and hot water. We did not have a single issue like that. If I had to give one criticism, it would be of the check-in process. You have to go to a sister property that is about a 5-10 minute walk away. Once there, you punch in a door code and then a lock box code. While we had no issues at all with the process (we left our kids waiting with the luggage while we walked unencumbered), if you had to make the walk with luggage or small children after a flight, it may be inconvenient. Also, we only had one set of keys. Two would have been nice but we made it work with one set.
Overall, a truly fabulous stay! I would definitely recommend to others and would stay here again myself.