Please be aware that file uploads made via Formidable forms (Pro) are visible to public - i.e. the files can be downloaded by anyone using link
That may influence your decision to buy commercial license.
The company refused to acknowledge the problem. At this point, I am using my own hacks to overcome this, but if I knew that before committing to this component, I would have chosen a different plug-in, or at least would be aware that it will take much more work to work around their bugs.