I've heard lots of good things about Sushi Suma, but last time I went into that area for a feed there was the usual queue out the door and it had just started to rain, and seeing as I was with a group and wanted to have a relaxed meal, we decided against waiting. Me thinks I might have to go in there for lunch one day soon. They don't kick you out once 2pm rolls in, I hope?
If you want Teppan Yaki, there was a great place in Parramatta/Harris Park right next to Harris Park station called Okori (or something similar). Not sure if it's still there.
Dammit, haven't had a good sushi or sashimi meal in ages.
I've also had an awesome Chicken Karaage at a little place in Bondi (away from the main street/beach), but I think it was also Korean-run - the waiter was, anyway, and couldn't speak any English, which made ordering difficult.