I am trying it out given all the praise.

• I can't create more than 5 (!) tags in the free version
• it can't export notes in anything else than borked text files in the free version (formatting lost, no markdown, no pdf, no html)
• it doesn't let me choose where I store my notebooks, in fact does not tell me where it saves them at all
• backup files are not human-readable, they don't appear to be zip files in disguise, they are seemingly locked to notesnook (".nnbackupz")
• the importer/converter is on the web, and requires me to upload all my plain text MD files for conversion

I use QOwnNotes on the daily, which does not have any such limitations. On the other hand, it's a markdown editor, which means your monitor space is divided by two : it has separate editing & preview panes. It's honestly a bummer because apart from that it's pretty much perfect