Jaffa,
I believe it would depend on what is being converted... such as, do you want to be able to convert documents to pdf's or images?
Also, while Digital File Pro won't be able to convert it to a PDF, I think there is a way in PHP to convert documents to PDF... I remember being able to generate a PDF on the fly from another file while writing ColdFusion apps but I have never had to do in PHP but I think I read somewhere that it could be done... does anyone else have any input on creating PDFs with PHP?