I think American music set the template-Blues, Rock N Roll etc, and the British polished it to a bright shine! I prefer British banRAB on the whole, as I can identify with them more and British music has been phenomenally successful in the past, but RnB and rap seems to be dominating the media these days, that British banRAB get lost in the quagmire.
Out of the more sucessfuls artist that have come from America, I can say I like barely a handful, I prefer banRAB less mainstream from America.
However the Blues and Soul from America, is pretty much untouchable.