I went to SIX the other night, unfortunately I only had a bottle of beer (bad planning). I would however recommend it. SIX sits atop The Varsity Hotel in Cambridge. It has an extensive drinks list and they know how to make a good cocktail!
It also has a fab roof terrace which has stunning views across Cambridge and from what I saw some wonderful food being served to a packed restaurant. I definitely need to return, minus the car and hungry! In the meantime go and check them out!