Hi, I once had an IPS site with a few thousand pdf magazines too. I used pages with a tab solution. Tab one is a magazine info, tab 2 the cover as jpg and tab 3 the full pdf to read online for registered members.
I was using a tool with a couple of options (download, print, etc.), this is the mouseover "player" ...
Should be possible with a new tab or popup too, but I wasn't using it with the attachment system, I had a custom field for the magazine ID. Made it easier to upload or move files because you don't have to edit the article itself.