If I could only choose one, WHIP. Keep baserunners in the dugout, prevent runs without question. Obvioulsy, if a guy gives up 4 homers, and that was the only baserunners, he'll have a good WHIP but still give up 4 runs. However, that's like saying a guy can have a WHIP of 3.00 and give up zero runs. It just doesn't really happen.