This was my first experience using Airbnb and it was a great one. The checkin was seemless through a lockbox system (which is in a 24 hour convenience store) which was ideal for someone using less sociable hours for their flights like I did.
The location is great only being less than a five minute walk to higashi Nagasaki Station then only a 5 minute train journey to the ikebukuro, an ideal platform for most journeys.
The flat has just about everything covered, good bathroom facilities though nothing that will blow your mind technologically is solid, clean and works reliably.
The beds are all good, strong and comfortable. I will mention they are all of a 'Japanese' style in terms of mattress, so it may take a night to get used to in comparison to 'western' styles. They all however came with clean bedlinen and spare should it be required.
The flat comes with a couple of very handy guides which were of great help for how to use things like the washing machine and navigating the local area.
In short, great apartment, great host and if you plan on staying in the city I would suggest booking here as its a hidden gem.