Nice hotel with nice staff.
15 min walk from nearest train station, trains at 30-min interval, so driving would be a better option to go here.
Nice onsen baths, both private (in room) and the public ones. But the shower inside hotel room is also outdoors, so it could be cold during winter.
Also, if you are arriving early, I would suggest you to inform the hotel earlier, as the hotel main door was locked when we arrived at 1pm.