We used IssueM to create an online magazine site for an association magazine that didn't have one yet. You are right, it takes a bit to get to know how things are supposed to work, and our final site doesn't quite have the interface I would like (which to be fair is probably as much about my talent as it is anything to do with IssueM). One thing we did appreciate was how it let you have PDF only issues in their system - our client had a large archive of issues, but didn't want to pay to have each article put into the system. So, we have the newest issues online in full, with their archives added as only PDFs. Client happy, and not facing a huge bill.