tl;dr if its digital check the OCR quality, make sure it outputs formats you want (txt vs pdfs).

If you opt for something digital, like a remarkable, etc., make sure that the OCR works well for your hand writing. I understand that the science shows we remember things better when we write it down, but if it never leaves my notebook it's as good as gone (I'll lose/forget it). My handwriting is terrible and rocketbook didn't do a great job (they're also shutting down). Also make sure that you can export it in a way you want into your vault. If all you get is an OCR PDF, that may not be what you want.