The apartment is bigger than what it looks like in the photos. I've been almost a month and I was really good.
Seagull is a great host, always very helpful.
The neighborhood where the apartment is located is very nice and has everything you need: convenience stores (many!), shops, restaurants, etc.
By subway you can get quickly and easily throughout Tokyo and the station is a short walk from the apartment.
Really great choice for those traveling alone like me. I will definitely go back to Seagull for my next trip to tokyo.