Depends if you like strict traditional or more modern fancy stuff. I say this because there are many places in the SD area that are sushi places, but go over board on creativity into plain weirdness. I like the Sushiya chain. High quality for a good price. My favorite is Akita, just across town from me in Escondido, or Katsu in San Marcos. There are some excellent places in the downtown gaslamp area and Hillcrest/Northpark areas, but be prepared for a large bill and a long wait, especially on a Friday or Saturday night.