Sumosan has a very smart setting just off Piccadilly, with modern décor. Rock shrimp tempura had quite good texture but rather less so than the version at Roka (13/20). Unagi rice was fried rice with a little eel; this worked well (14/20). Wild mushrooms were fried with a rich soy broth, and retained their texture yet had absorbed the spices nicely (15/20). A tuna sashimi was supposedly blue-fin, but was inexcusably cold, just out of a very cold fridge. We left this dish until the end of the meal and it was still cold at the end, well over an hour later (11/20).
Yellowtail sashimi was of good quality. Soft shell crab avoided greasiness and worked well (14/20) but yellowtail with teriyaki sauce was rather dull (12/20). Overall I felt that this was quite good but less good than Roka or E&O, and significantly below the standard of Zuma, with which it is evidently competing. Service was reasonable but there was one mix up over an order that was handled poorly. £80 a head is a lot for food of this quality.