London is miles safer than Manchester. My sis went to Manchester university, the place where all the students live - fallowfield or somewhere like that was insanely rough looking. For her final year she lived with the parents and commuted 30 miles or so into Manchester a day, it's that grotty. Off licences where the cashiers are behind bank-style screens and bars, did not feel safe at all. By comparison the student areas of London, Hackney etc are quite nice. Only problem is London is a lot more expensive than Manchester.