Sin Ju has reliably fresh sushi, served elegantly in a beautiful environment. I wouldn't go there strictly for the food - there are other restaurants in Portland with fresh sushi at better prices -- but the entire experience is worth the visit. There are tatami rooms for groups, or you can sit at the sushi bar. The sushi chefs are normally very helpful and social.
Sin Ju does offer alternatives to sushi (tempura, bento boxes, teriyaki, udon), but I can only speak for the sushi. I have heard that the other dishes are quite good.
The one bad surprise I had was the minced garlic on the mackeral nigiri that looked like the expected ginger. Quite overwhelming -- it ruined one otherwise good meal.