We would generally stay at Dormy Inn for their natural onsen and be happy with their services & facilities.
It has met our requirements this time (good location close to public transport, shops, restaurants, quiet, good breakfast, communal laundry, etc). Somehow this was the first time that we encountered an issue with the Dormy Inn (or any other hotels for that matter): there was pretty bad sewerage smell in the bathroom (we were in room 612). As we only stayed for a couple of nights, we didn't bother reporting the issue or asking to change room.
Other than that, it'd have been a very nice stay.