Sushi Too is an excellent sushi place, but it is also affordable. The service is quick because for some reason no one is ever eating in there! Why?? I can't understand it! The food is great; the prices are good; the service is fast; plus, it is on Walnut street. I cannot believe this place isn't packed at all hours.
On one particular visit I ordered the shrimp sushi and one of the variations of their Oh My God roll. Everything was fresh (very important when it comes to sushi, duh) and the textures working together in the Oh My God roll were complementary -- crispy shrimp tempura, perfectly cooked rice, creamy top. Very very good overall.
Their lunch specials are also legit, so I recommend visiting for lunch. You get a lot of food for a very small amount of money.