My DD's is pretty even but my preference is at least slightly up and I think it's better.
1) I think it assists in getting a nice early barrel rotation/arc into the pitch path
2) I think it promotes better use of the hands vs. pulling the bat through the zone
3) I think it promotes a good launch angle vs an uppercut, especially on higher pitches
4) I think it promotes better use of the shoulders (rock the baby)
5) I think it looks cooler
1) I think it assists in getting a nice early barrel rotation/arc into the pitch path
2) I think it promotes better use of the hands vs. pulling the bat through the zone
3) I think it promotes a good launch angle vs an uppercut, especially on higher pitches
4) I think it promotes better use of the shoulders (rock the baby)
5) I think it looks cooler