[Zope] Design Q: Product vs. External Methods

Hi Zope-Experts, one question concerning design using zope: Assume, I have a bunch of python modules / scripts, which I want to make accessible via zope. Is it better to use the external methods to bring the python modules into zope or should I make a Product out of my python modules. I also would like to know, if it is possible to update a bunch of external method zope objects simultaneously, or do I have to click 'edit' on every single external method object after editing the corresponding python method? This would be a bit tedious with 30 or more external methods... Thanks a lot for any hints! Tilo