I have had the pleasure of coming to blowfish twice now for work functions.
The pluses: the service here is great (very friendly and knowledgeable.) and they have beautiful decor. The sushi here is amazing- the fish is fresh, the rolls are inventive and delicate and beautifully presented. In one case, we had a hand roll made of pink soy paper instead of nori, which was a delicious alternative.
The minuses: it is very loud here and tough to have a conversation. The entrances off Bay Street (and from the E&Y building) are really hard to find! And generally it is pretty expensive, so probably not a place the average person could come to often. Lastly, during my second visit one of the dishes we ordered - crab - tasted like it had not been completely defrosted.
Despite that, all in all, I would say that it's probably the best place to get sushi in the financial district!