The software on ebook readers seems awful, and the responsiveness nihil. Years of upgraded models haven't changed this. Reading PDFs was borderline impossible because in addition to being slow, my device didn't even cache the previous/next page... Even though there is ample time to do so while you are reading.

The fact that it didn't occur to anyone involved to do so should be all you need to know to avoid the entire product category.

In a parallel universe, a company would've treated e-ink as a medium in its own right instead of as a webkit front end. They made the same mistake that html/css did: locking in the capabilities before they understood what people needed it to do.