try todias
It's actually just called 'Todai', but I can vouch for this one as well. It's on one of the upper floors of Pioneer Place, and when I was younger, my mother had a birthday there with a good 10-20 people, and it was a very nice, classy restaurant.
If you're looking for world-class sushi I would recommend Murata, on Second & Market. It's about a 10-minute walk from the hotel, and a bit on the spendy side, but IMHO the best place in Portland.
Spendy doesn't equate to "world-class". If you want spendy, on quality japanese cuizine, there's a place on the east side, on Powell, I believe, called Ichidai. They are, what I'd consider, far more "world-class" than a restaurant that doesn't even have it's own website(or atleast one easily accessible via a quick googling.)
Also, for cheap sushi eats, there's a Marinepolis Sushiland on 10th Ave, a block and a half north of Burnside. They're a conveyor belt style sushi restaurant, where you can look and pick what you want, instead of having to order specific items.