This place is good to be an onsen, the onsen itself is really good, they have a place to stay if you don’t want to stay in the capsule and includes beverages, beer, wine, even popcorn, free amenities like toothpaste and toothbrush, q-tips, shampoo, razors and foam. The hall of the capsules smells like feet and I imagine why. Inside the capsule it was never a issue, they have a little fan and a curtain and if you want to go extra a little tv.
The only problem is you go need to go to first floor to your belongings. You can take a backpack with your stuff and let them in the capsule.
The capsule is comfy, they have the fan a little curtain to separate from the neighbors. If the lights from the hall bothers you, you can try to put the curtain inside and that solves the problem.
Everything is walking and is a great location to stay a few days.