I stayed in roof side room. In other reviews, some people said that room is small, bed is small, etc. I'm sure that it is very good enough, at least from Japanes standard. If you compare with luxury hotels, it is small. But I think it is not luxury hotel, as like as Ritz. Because it was roof side, ceiling is not high. But good enough for stay in. Of course, If I stay in for 1 week, I would like to stay in wider room. But I think it is good enough for 1 or 2 nights stay.
It was summer, and Lucerne was actually hot. And Air conditioner works properly.
Restaurant is good. It is not typical Swiss cusine, but good spanish restaurant.