They are essentially a rice bar, with their main offerings being rice bowls with various toppings (beef, chicken, curry and salmon), as well as a few udon and salad dishes.
There are pre-prepared sides to go with your meal: miso soup, takoyaki, edamame, karaage, spring rolls, tempura and daifuku. These are kept in cabinets close to the ordering station.
You can order straight from the menu, or alternatively there's also a complete DIY option where you just get a bowl of rice at the ordering station, then choose toppings from the self-serve area and pay according to what you've chosen.

The service is fast and efficient, with a semi-production line atmosphere. After ordering, you receive your rice bowl on a tray, which slides past the self-serve cabinets, to the cashier. After paying there's an area with cutlery, chopsticks, serviettes, water, take-away lids and a wide variety of condiments and seasonings. As well as the ground-floor seating, there's an upstairs dining area away from the hustle and bustle.
Whilst there are definitely cheaper options out there, I like rice workshop for its efficiency, visible quality, and reliability.