Chaya does good sushi, probably the best quality in the city. You're going to pay for that quality though--it's hard to walk out without spending at least $20 per person, and you can spend much, much more. They also have an assortment of otherwise-hard-to-find appetizers, which are solid, but I would recommend the sushi above anything else. I you get the seared tuna, you're in for quite a treat.