The place is really quiet and not to far from the stations. When walking from Ueno station, you will pass by various marts/restaurants which is perfect for a quick grabbing of snacks or meals. I think the room is good for 4-6 people, more than that you will not have enough space for the luggages. The only con I got is that the toilet is quite small and there is only one. We only got 4 people staying so it is not a big issue but I can imagine having to wait for showers.
In my trip, we rented out 2 floors of the building for 8 people, which is really nice for a big group so we don't have to find another place and meet up later. If we are coming to Tokyo again we are sure going to stay here again!