I tried various ones out over the course of a few years, but in the end found they weren't for me and I went back to using paper notebooks.

I won't say they're bad solutions at all, but just that they brought no actual benefits for my use cases so there wasn't a reason to put up with their downsides. The downsides are relatively minor, though. For me, they are cost, the need to charge yet another device, and the inconvenience of the form factor (you can't tear pages out to hand to someone else, they rigid tablets instead of flexible paper, writing on them isn't the most pleasant thing, etc.)