First of all, no wifi! just cable. I'd give it a 5 with wifi.
Keywords: Central location in Namba, very near Namba Station, nice rooms, surprisingly quiet, efficient service. We didn't try the concierge or eat at the hotel restaurant. Very good value for money.
It was strange arriving there, as it is located on streets that have a roof (called underground mall on the tourist brochures which I think is a misnomer, it's just a street with a roof). There's quite a number of pachinko parlours close by, the most I've seen in my travel around Japan. I woudn't call the neighbourhood seedy, but it is noisy and doesn't give a fantastic first impression. This might depend on your age :)