For AYCE Japanese restaurant, I would recommend Ninki Japanese Cuisine @ Scotia Plaza. It offers AYCE dinner from Monday to Friday 4pm to 9pm. The good thing about this restaurant is you have a choice between AYCE and regular dinner. The two menus are very simiiar and the quality is the same. You have to give up quality for quantity in most AYCE restaurants, but not in Ninki. It is so far the best AYCE I've tried in Toronto.