One of the most wonderful things I have ever heard. It sounds so beautiful on EVERYONE! Yes, it depends where in England the person is from (accents are different all over England), but generally everyone sounds amazing. British children can be throwing a tantrum and still sound adorable.
As an American, I am desperate to rid myself of my Jersey-ish accent and adopt a British accent; however, most British people are not too fond of foreigners attempting to mimic their accent. They will most likely see right through that accent you copied from listening to an interview of the Beatles or watching My Fair Lady and will either: (1) Laugh and tell you to stop (2) ignore you because they think you’re mocking them or (3) harshly frown at you and tell you your accent is terrible and fake. I have been lucky enough to speak to British people who thought it was funny, but BEWARE of the not so easy-going British man/woman.
If you cannot suppress your desire to attempt a British accent, try reading this book first!