When I worked in Tokyo 8 years ago, my boss took me out to an expensive sushi joint at the top of a Shinjuku hotel. (Hilton?) He expensed it, told me it was a few hundred dollars, and told the chef specifically what to make- no menus in sight. The sushi melted in my mouth, and I tasted roe I've never seen since. Also had some pygmy melons that seemed pretty tasteless, given their delicacy.

I would say this- if you are going to spend the money, make sure it is really a special, reputable place, and not just expensive for the sake of being expensive. I could certainly taste the difference, but I don't know if I would spend that much for a meal under too many circumstances.