I am a premium user trying to use Evernote as my personal knowledge base (PKB). I recently moved from trying other software alternatives (DevonThink, The Brain) because a variety of reasons. I really like Evernote's flexibility and superb synchronization across devices. I have a number of pdf files (both from personal and professional interests) that I am organizing with Evernote. Because I'm in the process of migrating my content, I'm halfway through my monthly 10 GB upload limit, and that's fine, I'm still have plenty of upload space. The problem is, after I passed the 4 GB limit, I have bee