When I visited the Yodabashi Camera shop (unarguably the biggest) at Akihabara in downtown Tokyo, I came across this chain sushi bar called Sushi Zanmai which serves good sushi at reasonable price. So, my friend and I secured two seats by the conveyor belt and started gobbling up the sushi.
I have forgotten the name of some of the suchi I ate but the identifiable ones were maguro (tuna), otoro (tuna belly), uni (sea urchin) and hotate (scallop).
The total damage done was ¥3049 for two persons. Not cheap by Malaysian standard but reasonable considering the high cost of living in Tokyo.