I'm a New York chowhound in London on business in mid-April, staying at the Charlotte St. hotel. I made this same trip last year, and ate at Roka and Passione, both of which I enjoyed and will return to this year. I also ate at Rasa Samudra, which I was disappointed in after the high recommendation it received (I found the food oily and that different items tasted too similar to each other). Anyway, I'd like to go to a couple of new places this year, and am looking for good business dinner (so upscale) recommendations in that area. Any suggestions?