I like the Ray/Kobe one. The beef was public, and they did a good job showing Ray's accuracy, but also the fact that Kobe was a hell of a player.
I didn't like the Calhoun/Calipari one. Too superficial. I think a big part of their beef was more personal. The public comments were both just taking little jabs at the other. I don't know how much was urban myth (Calipari's comments about Louie Carneseca, rumors of Camby getting paid to go to UMass, etc.), but Calhoun hated Calipari and it wasn't just because UMass got good and Cal isn't from New England.