UK, Ireland / Which are more alike -- Warsaw and London or Warsaw and Manchester? [7]

This is a question for Poles who've been to England, or English people who've been to Poland! My friend says that, if you were going to compare English and Polish cities, Warsaw is more similar to Manchester and Krakow is more similar to London. Is this true? I would have guessed it was the other way around, what with London and Warsaw both bring the capital cities, but she swears Krakow is more like London and Warsaw more like Manchester.

The thing is, my friend and I are planning a trip to Europe, and we want to spend a night in Poland, but don't know if we should choose Warsaw or Krakow. My friend (who's been to Krakow and Warsaw) says I'd definitely prefer Warsaw because I much prefer Manchester to London, but I find it hard to believe that Poland's capital city won't be more like London!

Which would you say are more similar -- Warsaw and Manchester, or Warsaw and London?

Thanks. :)