I found the old XP method kind of irritating, especially in the way it both encouraged and enabled the "Oooh look, experience, I attack it!" mentality. . . .to the point where one player got sick of us mocking him with the phrase "I long for experience" (Said in the voice of a protos zealot). . . or worse, when taking a low end survivable E crit exclaiming "Oooh, feel the experience!" (Taking Nietche to a new level)
The whole "Kill it, bag it, count it, and level up" method encourages the lowest common denominator of combat monstering, kill stealing, treasure hording sociopathy. . . .Which is amusing in it's place, but core loading it into the game seems to be begging trouble.