I don't buy into the WAR arguments. WAR is subjective. There are three seperate sets of standards for WAR. None of the three are accepted across the board by baseball. I accept there is some value to using WAR if a standard can be set and eliminate as much subjectivity as possible. Right now WAR is no less subjective than any debate between two people arguing over Trout versus Cabrera and vice versa.
While I recognize Trouts fielding and baserunning advantage over Cabrera, the MVP is usually thought of as a hitting award for a player on a winner. While there are newer Sabermetric stats of some value Caberea accomplished something that had not been done in forty-five years. These three stats are the hallowed stats of baseball. Second, Cabrera's team is in the post season. If this wasn't enough to turn me to Cabrera I would add in the sentimental value of Cabrera has been putting up numbers for years while flying under the radar screen while Trout should have many more opportunities to win.
Stats I look at to help decide the productivity of hitters is total runs and rbi's, OPS and Avg w/RISP. Cabrera's OPS is thirty-six higher than Trout. His Avg w/RISP is thirty-two points higher than Trout.