I'm a fan of Zen. They have good service, great sushi and holy crap the salad dressing!
You know that Japanese salad dressing that comes on pretty much all the salads in pretty much all the sushi places in town? You know how it's really good? Zen seriously has taken this dressing and done some sort of magic to it making it heavenly. I never thought I would be so impressed with leaves and sauce, but Zen has made me a believer.
They are also exceptionally good at sushi. The fish is always fresh and succulent and the rolls vary from the normal California/spicy tuna/vegetable into Alberta rolls with smoked salmon, a yam tempura roll that is anything but ordinary and spider rolls that make you want to overeat.
Zen is a great place to grab a sushi boat before you head out (or after you are done) shopping in the core or to catch a bite and some sake after work; and because everything is so fresh and delicious, you won't feel bad stuffing yourself silly, leaning back in your chair and ordering just one more salad and spider roll.
T.