Well, he's a big, explosive CB. And he plays with great balance. He didn't have the quickest feet at the combine, but he did a nice job of staying low. He does a great job of using his body to box-out (legally) receivers. Also, he has a big recovery zone - thanks to his speed (4.41) and leaping ability (40.5" vert, 11' broad).
He sucks at tackling, and he obviously hates tacking. But he's a great cover corner.
A lot of people were surprised by Milliner's 40 time. Didn't think he was an especially fast guy. Not saying they're right or wrong, but there were those people. I don't think anyone was surprised that Rhodes ran a 4.41 or put up any of the explosive numbers that he did. In the way he moves and covers, he reminds me of Pat Surtain - if he were bigger and more explosive, and I am a huge Surtain fan.