As a place to sleep for one night if you're exhausted from working or partying and can't afford a long taxi ride home after midnight, this capsule hotel is serviceable. The beds and toilets are fairly clean. Though the capsule space is shared, it's quiet enough for you to get a good night's sleep, even if some of the other patrons snore through the thin curtains. Unfortunately, that's where the positive qualities end.
The hallways throughout the hotel smelled of cigarette smoke, even though there are only certain designated areas. It's as if the hotel has no ventilation. The common room (which also stinks of cigarettes) is fine if you're doing work, as there are a couple of tables, and it's the only area in the whole hotel that has wi-fi. It's not the best places to relax, as the couch and sofa chairs are really firm.
I would NOT recommend this place for people who are working late. My friend and I were working late nights and were hoping to sleep in. On our first night, we were unwelcomely surprised by the cleaner, who knocked on our curtains and drew them up hastily. He kept repeating the word "clean" while walking up and down the corridor, forcing us to wake up. This happened each of the three mornings we stayed there. Everyone else staying on the floor had already gotten up and left. Basically, it is a strict hotel rule that they have to clean the capsule beds around 10 am (I think there is an exception on the second floor). We asked for permission to sleep longer, and the staff would not allow it. It doesn't make any sense if one person is staying in a capsule over an extended period of time.
The other problem is that you can only shower in the public bath, i.e. onsen, on the top floor, which is only available early in the morning between 6am-9am and 3pm-12am. You can use the onsen in Asakusa for about ¥500, but it's a bit inconvenient if you've got a bunch of plans for the day.
The people working at the counter were mostly sullen and unfriendly whenever my friend and I approached. We never felt welcome. It feels as though they are resistant to westerners coming in. When you enter the hotel, there's a fairly laborious process where you have to take of your shoes, put them in the locker, then give the locker keys to the receptionist. I respect having to take of your shoes when entering certain indoor areas, but this procedure is frustrating if, for example, you forget something in your capsule and have to run up to get it.
If you want try out the novelty of a capsule hotel, I suggest trying one of the other ones around the city. It's much cheaper to stay the night at a love hotel, and from what I've heard, much more comfortable. The Khaosan Origami Hostel is nearby and offers a comparatively luxury hotel experience for the same price. When the day came to check out of this place, we couldn't wait to leave.