Nijo is a decent Japanese close to the DT office and is a great value to boot.
The sushi rolls are huge and quite are pretty good and fresh. I think their shrimp tempura roll is my favourite.
If you buy a large order - there are some freebies like edamame, which is actually pretty good too.
I have never come here for a dining experience - but the take-out experience is pretty simple and a breeze and the staff was quite friendly and patient.