Basic Toyoko Inn level: room is clean and normal Japanese size (=small in western scale), hotel staff speaks English moderately, breakfast selection is modest. Nothing special, but basic needs are fulfilled well and in an affordable price.
This hotel's location is very good for exploring the city. There are some restaurants and konbinis in the area, and Tokyo Dome with its smallish amusement park and shopping possibilities, if that interests you. But the best aspect in the hotel's location is the selection of public transportation. The nearest entrance to Korakuen and Kasuga stations is just opposite the hotel door and there are four metro lines running from these stations. It's very easy to get to any direction in the city.