I had the pleasure of visiting Oishii Sushi for the first time - I was in Boston on business from New York. It reminds me a lot of Japonica in New York - so if you're an Oishii fan and you happen to be in NYC, try Japonica on University Place for similar quality and portions.
Being new, I ordered my usual thing of green tea, miso soup, and the sushi-sashimi combo with an extra order of uni sashimi. The uni was briny-fresh, and just lovely. The combo was HUGE - I barely finished it as it was. Very fresh fish, and yes, I am fan of big slabs of fish. My companion was more adventurous and ordered "The Maki" which was seared toro wrapped around eel and avocado with small slices of jalapeno and dollops of mayo - YUM. He also got the Hotate Tokayaki; pieces of scallop mixed with mayo and broiled in a huge scallop. Very rich and very good.
Next time I'm in Boston, I'll be sure to return and try more things!