I now have 3 dasung paperlike pros, all the 2nd gen not 3rd gen Paperlike HD. I am really pleased with them, but if you are buying a used one you should know that there have been several revisions of the Paperlike Pro and my newest one is better than the second newest which is better than the oldest. I am happy even with the oldest one, but it can not change mode with only the hardware button like th other 2. I do not use any driver with them, so the option to change gray-scale mode with the button is really desirable.
there is one negative to consider: the screen is shiny, and they provide an anti-glare film that must be applied by the purchaser. This should be done in a super dust free environment with a great deal of care or else there will be trapped dust and bubbles. I can tell from videos of the Boox Max 2 that the lag is much greater than the Dasung. I don't notice any lag on my paperlikes.
I had no symptoms at all for almost 2 years then a brief period of symptom caused by what i think was a high frequency sound issue or maybe overhead lights but after leaving that environment and using only Eink, I am basically 100% symptom free. No sleep issues, not loss of apatite, no allergy like symptoms, no anxiety, no eye strain, no visual snow, no headache, no issues with Ehem.... relations, no memory problems, no confusion, no feeling like I am going crazy, all gone by avoiding LCD (and flickering overhead lights) (and maybe very rarely super high pitched rythmic sound)