We went to Gyozas center after saw it in Lonely Planet guidebook.
It seems the place burned and they are running a temporary place. Only take away is available but with a room to dine in.
The problem was not the premises.
The gyozas are very greasy, moreover, even it's indicated there is pork and lard in all gyozas, we cannot find any meat in it (see pictures, "cabbage and pork" and "stamina with garlic" types).
We told at the counter and to the cook, there is no meat, they said there is a "little little" pork! The cook show us the bowl with mixed vegetable and pork, and yes there was a "little little little" pork, almost nothing.
We like veggie meals but we like also to have what we pay for.