Harmon is great in NCIS, but he doesn't fit my idea of Vaughn.
He doesn't exactly fit my perfect idea of Vaughn, either, honestly, but he's the closest I've come to finding one. When I saw people suggesting Boxleitner for Vaughn, I just couldn't see him in the role. Harmon is more... serious, I guess. Vaughn isn't as gruff as Gibbs on NCIS, but Boxleitner just seems too... lightweight to me.
But then, how are we ever going to find someone who's basically Sean Connery without the accent? lol