The 5 of us loved our 9 night stay in this beautifully furnished unit and loved the ambiance of the hidden alley. It was so close to everything and extremely walkable, and the Leicester Square tube stop was only 3 a minute walk for longer trips. Even getting to Windsor Castle only required 1 train change. Having the Tesco grocery store around the corner was fantastic!
As others have mentioned, there are many stairs (~40 from living room to top floor bedroom) plus stairs down to the kitchen. That gave us all a workout! The internet never worked in the snug and was spotty in the dining are, which was somewhat problematic for my kids who were working remotely, but we managed. Also be aware that the Harry Potter walking tours that stop for a few minutes in Goodwin's Court several times a day can be rather loud, depending on the group size.
All in all, this was a great place and we would stay here again!