My two teenagers and I spent 17 nights at Paul's place and we loved it! Not only is Paul a lovely, interesting and respectful host but his flat is clean, spacious and in an impossible-to-beat location. Within 5 minutes walk of Lancaster Gate and Paddington stations; less than 5 minutes to the entrance to Hyde Park; close to grocery stores and a very very safe neighbourhood no matter the time of day or night.
The flat itself is very large for London -- we had plenty of room, and were all very comfortable. Honestly this is a fantastic choice, I highly recommend you book it!