I went as part of a big group trip. I felt like it wasn't worth the money spent. They had all the classic Japanese food/drinks such as green tea, green tea ice cream, etc and of course sushi but it wasn't amazing. The store's kind of small but that might've just been because of the size of my group.
It's also quite a walk there from the station. It would be convenient if you lived nearby and/or doing your shopping at woolies.

Okay sushi if you need a quick bite before or after you do your big grocery shop. There is not much variety on the train but you can request items off the menu. My fave is still the sushi train in Miranda.