Check out the nomlicious Shiok Maki from Koh Grill & Sushi Bar! It's really tasty, I believe due to the flavouring of the sauce (somewhat like the flaming sauce served in the Manhattan Fish Market).
Koh Grill is pretty much busy everyday, and I would recommend you to make a reservation so you do not have to join the long queue. It's a really nice place for a gathering as well.
Don't forget to order the Shiok Maki (original version) - a person alone can finish one portion by himself, so gauge your dishes from there! I've also tried their teppenyaki beef, it's juicy and really, really delicious. Not to mention their salmon sashimi, each slice is thick, fresh and *slurps*.
Koh Grill & Sushi Bar