How to avoid 3650 PMM corruption

Hi,

My 3650 just came back from NRC after I had 4x Nokia blimp (PMM
corruption). Now I am really scared of installing any applications
on it. Do you folks have any suggestions on how to avoid corruption
in fututre?
I was thinking if I could take a full backup of
my MCU+PPM+EEPROM+PMM. Later if I develop the same corruption, :rolleyes:
all I have to do is full restore. I have been doing DCT3 backup, restore
ritual after I screw up few flashes. Does that apply to DCT4/Symbian
phones also? I do understand I will need a Griffin or similar box.

Thanks
-a