I'm one of the minority who prefers him as an anti hero. He's the best anti hero ever in B Town with the flicks like Don, Anjaam, Darr, Baazigar etc but he's accepted by fans more for his romantic movies
Like Aditi said he's not good looking. Not this tall handsome guy who every gurl would die for plus but he has that charm which nobody else has on screen. When he looks into the eyes of a gurl and says he loves her, he means it. I guess that's what makes him so special