Mr. Brooks vs. The Talented Mr. Ripley
Lots of similarities here. They do everything almost perfectly but still manage a couple of oversights ("Ripley's Game" for instance). So the question is: "mano a mano", who would win? (Kind of like Samantha of "Bewitched" vs. Genie of "I Dream of Genie", or "Alien" vs. "Predator".) They are both insufferably arrogant.
Perhaps the only difference is that Mr. Brooks is insane while Mr. Ripley is just a sociopath.