Stayed here for three nights during a solo trip during winter. The rooms are small as reviews suggest, but exactly as expected and in-line for the location and price in Tokyo. Front desk staff was great, rooms and bathrooms extremely clean with bidet toilets, and AC was good. I really enjoyed the open-air rotenburo (hot spring bath) at the top of the hotel! Timing for male and females rotate, and as a result, you need to go to the front desk to change your room card for the 11th floor card, but it's easy and worth it.
Also a pity that impressive views of the SkyTree are blocked by the high walls, but I can understand that for privacy reasons. Only met one other person the 3 times I went to the hot bath after a long day out. Otherwise, walkable from Metro stations (about 10-15min if you don't mind walking, but perhaps not the best for people who can't walk as much), good value, right beside a small supermarket, and great views of the Tokyo SkyTree from the main road. Nearest tourist areas are Ueno and Asakusa. Front desk also helped hold my Amazon packages I delivered to the hotel, and also allows baggage storage for pre-check-in / post-check-out.