i wouldnt recomend it. Colleges like teachers better. My brother tried to get a alumni to do it but he said it is not as important to colleges because teachers have more excperince with righting them.
letters of recc are sick if you get a good one...find a teacher you had that you enjoyed and have them write you one...from any grade...i had my 8th grade US history teacher write me one worked like a charm...
my buddy is dating the super intendant principals daughter so he got a prime time one ha.
If you get one from an alumna, make sure they contributed to the university, like they were the rector, or on the football team or just give a shit load of money.