Nippon is a great place to grab some quick sushi. You can either pick up already rolled sushi (which I never get), or order what you want and it is made fresh in front of you. The choices are pretty decent for the size of the place.
I normally grab a couple rolls of maki to go after a nice workout at my gym nearby. They are very fast and the sushi is definitely good. It is a bit more pricey than the other quick sushi shops, but it is definitely worth the slight increase in price.