Great little Japanese market that I have visited dozens of times over the past ten years... pretty much a one of a kind in the Pittsburgh area. The owners and shopkeepers are friendly, and the variety is pretty extraordinary for such a small space. Fresh sushi-grade fish is available, either chilled or frozen. Unlike some other commenters, I have never experienced the fish being "off"... always great quality.
Sushi and bento is made on site by the owners, but only expect a large variety right around lunch and dinner time.
Stop in, if for nothing else to try some of the authentic Japanese snacks and drinks (including hot coffees and teas up near the register). If you are looking for authentic Japanese cooking supplies, they have all the staples.
There is a pretty good sized shared parking lot that is often full. Parking is also available in a small lot around back, and on the surrounding streets.