It has been a while for me to go back to the one at Nishi-Azabu but have been to the one in Shibuya a few months ago.
Food is not bad still but in my honest opinion, the quality of cetain dishes has been down.
Some of their sushi rolls are nothing like traditional Japanese Sushi but you might enjoy it if you are too scared to try something completely Japanese.
Atmospher wise, Nishi-Azabu is better than Shibuya but longer walk from the nearest station.