I know this is going to sound really dumb, and prob will lose my stats credentials, but I have yet to find an advanced defensive metric that I think is worth much of a damn. I mean, when it comes to defense I think the "eye test" and scouts grades are truly the best way to measure. Though I am a big fan of advanced metrics for hitting and pitching, nobody has done a good job on defense and thus the more I look at WAR the more and more I find myself ignoring it. If I haven't seen a guy play defense much live/on TV then I will just go off a scouting report or ask someone else who watches enough games. It doesn't take a genius or huge sample size of games (50?) to realize if a guy is Amazing, Great, Very Good, Above Average, Average, Below Average, Mediocre, Bad, Poor, Delmon Young in the field. Perhaps maybe we should start figuring a way to grade a guy defensively on an F to A+ scale and figure out a way to assign "value" that way? Arm+Range+Speed+IQ all included, then perhaps you weight certain positions differently then others: i.e. SS, CF weighted more heavy then LF/RF/1B.