Tokyo Japanese Food Store is the only Japanese grocery in the area with a nice selection of produce, fish and processed foods. Not all, but many things are overpriced, and I would check out Lotus (Asian market) in the strip district for certain items such as sauces, noodles, etc.
They are known to sell things past expiration dates: sometimes in the form as a "sale" without explicitly notifying the customer of the condition. Now, I don't have a problem with buying slightly expired non-perishable (boxed, canned) foods for less... but I expect an honest business.
Many of their raw fish look discolored and old, making me ponder the honesty of the packaging dates...
In the end, many of the Japanese items can only be attained here, in Pittsburgh - having a small, but formidable selection to suit your needs. I would just be weary with expiration dates and the perishables they sell.