I'd concur with that score, with one quibble: the rice boxes at Oisi Master simply aren't very good (especially compared to the efforts, of, say, Red Star Noodle Bar on Cowley Road).

Specifically, if you remember I had the fried chicken and curry sauce rice box, while you had the fried chicken and curry sauce with plain boiled rice on a plate, and if you recall you got more chicken and more curry sauce than I did, while they stuffed my rice box with far, far more rice than the meal actually merited. It was nice enough stuff, but it left me wishing I'd just ordered more sushi.

That makes sense... In fact, I'd say it was far worse chicken katsu than rice box, and it was more expensive. I did indeed wish I'd concentrated on sushi. I did pay rather more for mine than yours though - my curry cost the same as your box in total, but I had to buy my rice as a seperate side order.