Just a heads up, I have visited quite a few of these in my time (I travel alot) and while as a fast food chain they are better than most since everything is either steamed or grilled, and they use loads of veggies....

THEY ARE NOT JAPANESE. Nost of the food they serve and the ingredients they use is in fact CHINESE, not Japanese, even though they advertise as "Japanese Fast Food". The few exceptions on their menu that is actually Japanese are:

1) The sushi of course...
2) The udon soups, however, they still put in veggies that are predominently used in Chinese cooking.

The reason I say this is that they used to be very good, and had a completely Japanese menu (and still fast), but in the fast 5 years they have slid into using Chinese food on half their menu.

I was alerted to this when things just didn't feel right, so I ran home and checked all my recipe books and reference material.

How to tell:

The overuse of cabbage:
While the Japanese do use cabbage, they do not use it very often. The prolific use of cabbage harks back to WW2 when money was low and the poor "had to use" the cabbage in order not to starve. While they could be using it to say, "Hey, it's fast food, eat what you get!" most restaurants, even "fast food" ones that say they are authetic or traditional would want to stay away from the image that using cabbage would send, and most Japanese would not want to eat there. Bento Box uses cabbage in literally everything and with great gusto. Before, when the place first opened, they used typical Japanese veggies, or better quality Western ones that were very close, but now you have to search for that tiny piece of green onion.

The overuse of bean sprouts
I have never seen bean sprouts used in Japanese cooking. At least, not cooked to something barely recognizable. I have, however, seen this in Chinese cooking.... lots....

I'm not saying "Don't eat there" but I am saying don't be suckered into thinking that the Bento Box is authetic Japanese Fast Food (because it isn't) just because their sign says so. They do have some good qualities outside the false advertising: The veggies are fresh, the food is fresh cooked on a grill in front of you, the rice is steamed unless you ask for fried rice (another Chinese invention!), and the sushi (depending on the "cook's" skill) is actually quite good, and fresh. The Udon soup is passable, unfortunately you have to ask for them not to add the veggies or it's just gross.