I work for a large NHS Trust in the UK and we are using Healthshare and we process 1000s of messages each day. Many of these are standard HL7 messages however for several months now we also pickup and drop off 1000s of PDF files.
We have our message purge set to 365 as we have to keep a years worth of messages as we have a retrieval and send process that enables us to replay any set of messages to any destination which we use to prepopulate end systems with activity and result history.