Not sure if people have seen these but a mate at work just showed me his: https://remarkable.com/
I bought an iPad 2 with the hopes of using it for sketching but never felt comfortable with it. This however feels really nice. It's fast, accurate, and pretty simple to use. You can switch the background out with grids and isometric patterns and only being grey scale doesn't worry me.
Nice enough to replace paper for me I reckon but it has a couple of downsides. It's e-ink which means the background is grey, i like white. It's as expensive as an iPad with less of the functionality (might be a good thing though).
Anyone else used one?