We spent four nights here in February 2025, with Diamond status. We booked a "Premier" room with a king bed and accepted an upgrade to a "Deluxe" room, which was around five square metres larger.
On most points I'd agree with
NZJuniorDoc. The room wasn't very functional (which is odd when one considers how good some Japanese hotels are at squeezing everything you need into 13-16 m²). There was no desk, only one chair, no wall hooks for coats. We did at least have a metre to pass between the foot of the bed and the wall.
Our welcome amenity consisted of two tiny cakelets -- not quite a bite each -- that weren't worth photographing. The welcome drinks had to be selected from a special list. Diamond status meant we at least got the "Premium" welcome drink list, which was a mixed bag. Whisky lovers could choose between a few named brands, whereas the other options included descriptions that didn't inspire much confidence at all, such as "Glass of sake" or "Glass of red wine". One of the three craft beers wasn't available, we tried and enjoyed the other two.
Our upgraded "deluxe" room was a corner room on the ground floor. If I'd thought for a moment, we wouldn't have accepted it: the two outside walls meant that we needed to have the forced-air heating on almost constantly. (Outside temperatures were below zero at night.) In summer there might well be a similar need to cool a lot, given the large south-facing window.
The location is excellent. Our room and the public areas were clean and well maintained.The staff we encountered were all helpful and competent.
We'd only consider staying again if a suite was available at a decent price using SNUs.