I have to make a choice between George Eads and Vincent D'Onofrio.
It's a decision between slashability and thinking =P CSI tends to spoon-feed the story, you never get enough information until the end to make a guess at the BadGuy. L&O:CI keeps you guessing throughout the episode. So I watch CSI for George and William (Gil) and L&O for the story, and how Vincent acts like a semi-Columbo =)
Oddly enough, I can catch enough of each since they play during each other's ad breaks. And isn't that a sad state of affairs that adbreaks are that long =P I fondly recall the days of 30sec adbreaks. You'd get one, maybe two, but then back to the show...