I tried Saizo in Sunnyvale last week on the recommendation from a friend in Japan, actually on the day that I had just arrived back from Tokyo, so my taste buds were still pretty discriminating. They serve authentic, home-style Japanese cooking. It's a clean, well-lit, tastefully decorated place but still casual just the same. There is counter and table seating with an open kitchen.
I was impressed by how they have preserved taste authenticity in such a competitive market. It's truly a pleasure to actually dine at a Japanese restaurant in California that hasn't Americanized the dishes or flavors (no sweet, thick teriyaki sauces there). I've also taken various friends and family members there and everyone has been very impressed. A nice touch includes the use of all ceramic dishes and bowls (even the miso soup is served in a ceramic bowl). It seems that they have really paid attention to detail.
Very reasonable prices on par with Gombei or Azuma (for those who know those establishments).
592 E. El Camino Real
(In the Pavlina Plaza Shopping Center a few doors down from Albertsons at the corner of Remington/Fair Oaks and El Camino)
Sunnyvale, CA 94087
Weekdays - Lunch and Dinner
Saturday - Dinner
Sunday - Closed
Call for exact hours