What range of schools are you looking at? Berkeley is the most notorious for this in the T14, along with a few others. And what actual numbers are we talking about here?
More personality v. shorter length - Do admissions officers prefer a clean and concisely met minimum (two pages, for example) over a half-to-full page longer personal statement with more emotion and personal background to it?
... I had seen was two pages so I made mine exactly ... two pages so I could use it ... be sure it's four pages that are equally good and ... alternate PS that is two pages long. Of course, if you ...
I think some of the ties in the T25 (2, 4, and 8, 20, 22) will disappear due to the hits that different schools had to take to their LSAT medians. I think Stanford and Berkeley both drop since they took hits across the board.