People from different culture may think that we can eat most Japanese dishes like sushi, tempura, soba, shabu shabu, ramen, teppanyaki, etc. all together at a Japanese restaurant. Indeed, I have seen many such Japanese restaurants in other countries. But here in Japan, "Japanese" restaurants are divided into each category, for instance, sushi restaurant, soba restaurant, ramen shop, etc. and if you want to taste sushi, of you need to go to a sushi restaurant. Sushi restaurants vary widely from casual and cheap to formal and expensive... Honestly speaking, I seldom go to formal ones but often go to casual one.
Near my house, there are two branches of "Tsukiji Shushi-zanmai (つきじ喜代村すしざんまい)", one of the biggest sushi chain restaurant. This chain seems middle between rolled sushi bar and traditional sushi bar. The atmosphere is casual. If we want to eat sushi, we stroll into one of the branches at anytime. Price is very reasonable but professional sushi cooks always make good sushi for 24 hours! Thanks to that amazing opening hours, we've been there at 4 am in the morning.
Any kind of sushi is recommendable, but tuna is very nice. The best thing there is we don't have to care about the bill and we can eat sushi as we want. It is wonderful, indeed. (Actually, sushi is not so cheap..) My rating is 3 out of 5. Gochiso-samadeshita!
Tsukiji Shushi-zanmai (つきじ喜代村すしざんまい) Yushima-branch(湯島店)