The rooms are absolutely gorgeous, really warm (we went in November) and the futon bed was comfortable. The room was large enough for a large suitcase as well. The room had a view of Mount Fuji which was breathtaking.
The staff were really helpful and accommodating.
We didnt eat in the restaurant as my partner has coeliac disease and unfortunately they couldn't cater (but did have gluten free options) but it smelt incredible.
The onsen was lovely, there were separate facilities for men and women with lockers and sinks with nice toiletries which you can use. In each room was also a little bag with a towel and toothbrush.
One of the most considerate things was there was free hot and cold drinks (coke, sprite etc), ice pops, cupnoodle for guests which was such a nice surprise.
The only slight downside to the stay is the walls are thin but we had ear plugs and were fine. There were also pyjamas to use which were tracksuit bottoms and a sweatshirt.
I'd 100% recommend staying here, the views of Mount Fuji across the lake alone made it worth it but the hotel was clean, fresh, and thoughtful.