Dylan
Neil Young
Mariah Carey
Neil Diamond, especially when he is singing about ET.
Tom Waits
Dolly Parton
Clint Eastwood
George Jones
Van Morrison singing through his nose.
Bruce Springsteen could read the phone book and sound anguished.

Anyone different enough to be interesting will be bound to irritate someone. Its all a matter of taste. If they have sold a million records, and all of these have. Someone likes them enough to pay to hear them.