[XFrequentist]

This was a while ago, but IIRC there were some fairly major software-reliability rough edges (frequent crashing/bugs/etc). Beyond that the major shortcoming was that it was constrained to pdf's only, and that's only one part of my reading workflow.

For a while I was trying to sync a Zotero library (since I need citation management when writing papers), and do all my academic reading (which is mostly pdf's) in Polar, but it was just a bit too much overhead to stick with.

[roznoshchik]

Oh interesting. PDF's is what is hardest for me. I need a completely different approach to handling them than I have been using for web content and epubs.

Thanks for sharing your story, it helps to put things in perspective. I wonder how much they've improved since you used them though. The website looks very sleek.