Research has shown that heavy AA can lead to a mismatch between the putative beneficiaries and their peers. As a result, these students are more likely to end up in the bottom of their class (IIRC, 50% of black students at top law schools ended up in the bottom 10% of their class, and AA beneficiaries who planned to major in STEM were more likely to change to a non-STEM major).
So it is also possible that a preference that helps your kids get into a school could actually end up hurting them if they end up outmatched by their classmates.
I was accepted by a graduate program at one of the more selective UCs. An alum of my college who was a current student at the UC contacted me to invite me to a recruiting shindig for accepted minority students (she knew I was Asian from the club activities on my resume). But when she found out what my specific racial background was (half white and half Chinese), she said I would not be invited. The only people who were invited to the recruiting trip were those from other Asian backgrounds (anything but Chinese/Korean/Japanese), or students who were black or hispanic.
Instead of an all-expense paid visit spanning from Thurs-Sun and including sitting in on lectures, I was allowed to come for a single Sunday-only event. I spent more money on that trip than I had ever spent on anything in my life, except for my college computer. I was pretty ticked that the school was treating different minorities differently, and that for all the money I spent I couldn't even visit a class in session (since I was only allowed on Sunday). I remember meeting a half-Chinese / half-Vietnamese guy there, who regaled me with tales of the wining and dining that the favored-minority students had enjoyed.
I should note that this was way after Prop 209 (barring affirmative action at the UCs) was passed. I ended up attending the UC, and I asked an administrator about how recruiting trips like this were legal (he happened to be a lawyer). He gave some hand-wavey answer about federal pre-emption that, if true, would have completely gutted Prop 209.
So it is also possible that a preference that helps your kids get into a school could actually end up hurting them if they end up outmatched by their classmates.