Sushi and drinks were quite tasty, but disproportionately expensive, even for happy hour. I think this is common for the Mandalay Bay restaurants, but it was a bit shocking coming from San Francisco, or even from other hotels in Las Vegas.
Service and ambiance were excellent and definitely make up for the price somewhat, especially for snacks during happy hour, or for a meal if you've just won big in the casino or just want to act like you have.