It's wonderful! Best choice for a note app that I've made in ages. Every bit of core functionality is entirely free, it's only their syncing that is paid - and if you're entirely on a single device it isn't even needed.
Even for what I'm doing, I can just copy/paste my files between my PC and my Tablet and it'll be fine. I think long-term I'll pay the $4 USD per month to get sync, but for now I want to see how annoying it is to manually keep it up on each lol.