Let's convert WAR to a rate stat.
Ripken
Average of bWAR and fWAR = 94.2
PA's 12,883 / 600 = 21.47 seasons of 600 PA's
Average WAR /season = 4.39
Evans
Average of bWAR and fWAR = 66.1
PA's 10,569 / 600 = 17.62 seasons of 600 PA's
Average WAR /season = 3.75
So as a rate stat, Ripken's WAR is 17% better.