Sanraku is located in the Sony-owned Metreon complex*, a short complex from the W hotel. I actually walked by on Monday night and thought it looked a bit dodgy (typical cheap sushi place), but the following night, someone suggested we go there for sushi ("Not the best in SF, but good and quite reasonably priced").
Well, if there's better sushi in SF, then those guys have it very, very lucky. Sanraku was easily as good as the best sushi I've had in Seattle (at Izumi or Kisaku).
I ordered the omakase (chef's selection), which was incredible (and a steal at $38). It included several "appetizers": miso soup, salad with funky seaweed, monkfish liver sandwiching roasted eggplant, tempura prawn head. The sushi platter included fresh wasabi (yum!) and a great sushi assortment: tuna, unagi (eel), amaebi (sweet shrimp), gizzard shard, uni (sea urchin), toro (fatty tuna), giant clam, and 4 pieces of 2 kinds of sushi rolls.
Service was superb (handling a large table of tipsy people ain't easy).
Don't be put off by the apearance or location!
* They also have another location in SF.