This is the cheapest place for good-quality sushi I go to for the last (almost) 4 years. My grandma was the neighbour of some of the staff there and that's how we heard about it - at first I was skeptical (good, fresh sushi in Lisbon is hard to find at cheap prices)... then I went there to eat at her birthday. WORTH IT.
At about 12€/person at lunch (around 16€ at dinner) you get the full "à la carte" menu available to you with a wide selection of sushi, tempura, miso soup, vegetables, fried stuff (meat, shrimp, etc), stir-fry noodles, grilled meats and desserts (which I think is just fruit and ice-cream usually, it's the one thing you'll be more limited). You can order as many menu items as you want, you'll pay the same price! :)
I once even took a vegetarian friend there who feel in love with the place, so if you're vegetarian, don't worry: you'll be able to eat more than just cucumber rolls. ;)
If you're a fan of japanese matcha (green tea)- based deserts, you'll LOVE the matcha ice-cream. It's my favorite in the whole capital, since it's not so sweet that you feel like you're only tasting the sugar (which often happens since most people don't like the stuff). read more