I booked this when it was a new listing and there were zero reviews, on the basis of location and interactions with the host - that leap of faith was richly rewarded! Our family of four had a wonderful two weeks' stay!
Firstly, on our host Chris. He was prompt, and extremely helpful with the usual stay-related questions, and even more so on our special inquiries, including courts for playing tennis for our two boys. He was always available over email and text, and even welcomed us (and saw us off) personally, and very warmly.
The flat is lovely, and super functional. Anything you need is new, available, and runs very well. Chris made it even more wonderful by providing Oyster cards for easy transportation, and stocking basic groceries for a first meal - special mention for his wife's delicious marmalade and jam!
The location couldn't be better - in the center of everything yet quiet and peaceful. 2 min walk to Marylebone tube station, and 5 min walk to the better connected Baker St station, Uber drivers have zero difficulty locating the flat, and the Heathrow Express stops at nearby Paddington - a 2 min drive from the flat. Great restaurants / shopping / Regents Park at walking distance.

In all, fantastic flat / host / location!