Run'em till they drop
Faster is nice, but just about every new (dedicated reader) device has included a 'we know better' presentation feature that can't be fully disabled
Then there is the
cost reduction feature, sold as an
Improvement.
Eliminate those expensive/problematic buttons (switches) and further push 'Touch only' by eliminating other features (like any kind of audio on the K4NT. If my Astak can play a MP3 with only 10 selection keys and a slow ARM, the NT sure should).
Tablets are great for Manuals and charts, but they are heavy and have poor battery life. I see no need to use mine for the typical 'Great American Novel'