Simple Answer: Don’t go there.
Plone, despite its flashy coat of paint, is still a development work in progress. Upgrades from version to version have no guarantee except that they will be problematic. For now, and for many years to come, content management systems based on a relational database are the way to go.
More details later, but save yourself the hassle, unless your a python hobbyist that likes to mess around with code a lot.