I've had the opportunity to use a reMarkable in person, and it's the first and only digital writing device that I could tolerate to write notes. The MS Surface, iPad Pro and Samsung tablets have never cut it for me. It's difficult to quantify why - a combination of pen-to-display distance, latency and screen texture perhaps.
Reviewers seem to agree that the Supernote and Note Air have higher latency, and higher pen-to-display distance, so I wonder if I could work with them or not.
The reMarkable seems to to be the go-to device as a digital notepad, but doesn't do anything beyond that, whereas the other devices offer a (near) full Android experience, which would be more useful to me as a dwevice that costs £400+.