Umami flavour is key in Japanese cooking and the reason why it is so oishi. One of the historical explanations could be that because for many years before Meiji restoration four-legged animals meat had been forbidden, Japanese cooks had to develop other ways to bring out umami. Necessity is what triggers innovation and this is what has been happening at the high-end Edo-mae style sushi shops in Paris over the recent years. As the quality of the fish in Europe is never good enough for Japanese chefs, they have started ageing or pickling it extensively, which makes the sushi more delicious.
Personally, I really like Ginza Onodera in Paris, because the chef is hard working and a very genuine and warm person. (Their new London branch is a bad imitation of Zuma or Nobu though..) I would put Jin on the same level as Ginza Onodera Paris (the technical skills of Taku-san are incredible), followed by Sushi-B (rice consistency problems) and Sushi Okuda.
