London by a country mile. No contest. Many subjects are about personal opinions, but this is an objective fact that no one can logically dispute.
MK seems very good for its size, whilst Manchester is perhaps no 2.
There are certainly a lot of big cities which are crap. I can speak of Sheffield and Derby from personal experience (Nottingham is better than the pair of them together) whilst Leeds and Newcastle also seem decent, although I have no knowledge of them. Birmingham and particularly Liverpool appear poor, although again I have no personal experience.
I would tend to dispute it as "an objective fact". Finding a prossie, finding out what district she's in, finding out where that district is, then finding you have to get taxis there. And she charges London rates and if it's a blow out you have to go through the whole bloody rigmarole again.
What a ridiculous carry on just for a shag. Gave that up for a laugh ages ago. Stick to parties if I'm stuck in London.
And to think I won't generally book a prossie in my home town unless she's walking distance. London? You gotta be fucking kidding.
Those are what I would call objective facts and you have provided none. And I have logically not just disputed your assertion -- your opinion -- I have pretty well disembowelled it.