My twopenneth (for what its worth)
- the food in KM5 is excellent. Particularly the fois gras and steak Personally I don't think the drinks are particularly expensive. The wine list I found very reasonable. The quality of the ingeredients I found to be very good. The setting is lovely.
-the service is pretty rubbish. the waiting staff are all very nice, but take hours to bring your food/clear the table. Last year they lost our entire booking and we had to wait nearly 2 hours for a table

For this reason I'm not sure if I would go again.
- and for the record I'm not someone who just goes to poncy restaurants. I have eaten in little shacks in Kenya and the Caribbean as well as some of the top restaurants in London. I like eating in GOOD restaurants, and this is not necessarily related to cost. I do think however that if you are in a group that KM5 is an excellent option for an evening out. Just don't turn up starving hungry cause it might take a while to get your food