Ordered my M&P 40c without the magazine safety and with the external safeties (ambi). Never had a problem with ADs with my Glock, though one of our local PDs was rather famous for them. Just thought it would be a good idea for my next striker fired pistol, since I also spend a good deal of time shooting 1911's. Hope you friend has quick recovery, this is a lesson for all of us when reholstering our weapons.
Thanks,
Bill