What are experiences with different PDM Systems?

I am looking to implement a new data management system with my engineering group (~20). We use Solidworks primarily and sometimes autocad as well as some PCB layout tools. I have been looking at Windchill and Solidworks EPDM. I was wondering what are peoples experience with the usability of these (or other data management systems)? I am primarily concerned with how user friendly and robust it is for storing data and workign as a team. Project flow is not critical. Engineering change orders / notices workflow is a nice to have but not critical.

We have a large number of people in manufacturing that I want to provide access to PDFs of the drawings as a simple read only type user. I feel like there is often not a low cost solution for these types of user. What are your experiences?

Thank you.

SolidworksSolidworks Pdm enterprise Pdm