The legroom was just the minimum acceptable for a short-haul flight.

The cabin design and the seats were standard domestic Economy Class.

The snacks were minimal, and only a few soft drinks. coffee and tea were available.

The Economy Class was clean, but the rest was standard with minimal catering - this is the standard for domestic Economy Class in Japan.  2.75/5

The check-in was efficient and friendly, using Staralliance Gold facilities.

The stadard Economy seating offered sufficient legroom for the short flight.

The cabin layout and design were standard, and it all was very clean. 

No meal was served at all, only coffee and soft drinks.  This is a bit substandard, but not unusual for domestic flight in Japan in general.  The cabin staff were very friendly, helpful and efficient.  2.75/5