Airbag module replacement confusion.

[elgyqc]

I have read a lot of discussions on airbag modules and remain confused.
It is mentioned in many threads that the VIN number has to be programmed into a replacement airbag module, using one of Porsche's diagnostic tools. But there are a couple of threads of just replacing the module with a used one, resetting the error codes and all is good.
This is an example:
DIY: Airbag Module replacement & reset
So is the reprograming of the VIN really necessary?

My Durametric gives a list of codes for the airbag, but the important ones are:
"3 - Supply voltage
195 - Control module internal fault - All fault codes over 100 indicate a critical fault and usually require a new control module"

I checked the supply voltage and it is OK... so it would seem that the module is defective.

Thus my interest in replacing the module.