London has May many wonderful restaurants now including roughly 65 Michelin Stared Restaurants.Orchestrapal
We rarely spend for those, with exception of the very reasonably priced lunches in many of them and still eat extremely well for the weeks of our visits.
If you are a frequent visitor to London and enjoy our restaurants take a look at a website - Catherine's Hot Dinners. It lists and reviews many new and just about to open, London restaurants.
Some of the more expensive restaurants have 'soft launches' where they offer 50% discounts just before they fully open to the public.
Basically, you are a guinea pig, but I have been to some excellent places that I possibly couldn't afford if I had to pay their normal prices. Great if you can go for lunch as it is easier to get a booking than for dinner.