This is the point where musical historians start to diverge in opinion. For many, the whole of his subsequent work for RCA — encompassing over 20 years — was a steady letdown, never recapturing the pure, primal energy that was harnessed so effectively on the handful of Sun singles. Elvis, however, was not a purist. What he wanted, more than anything, was to be successful. To do that, his material needed more of a pop feel; in any case, he'd never exactly been one to disparage the mainstream, naming Dean Martin as one of his chief heroes from the get-go. At RCA, his rockabilly was leavened with enough pop flavor to make all of the charts, not just the country ones.