It's often done to help reduce brake snatch and judder on some cars, for what it's worth (I have not worked on an Aero remember) would be to try them as they are, if there is a problem chamfer the leading edge only, test again and then try the trailing edge. Logic of this is if you imodify before testing you will never know if there would have been a problem and doing it in stages you can track improvements if any? All your risking is labour after all. Have fun.
