[HarryT]

Early eInk screens were prone to fading - I remember than my original Sony PRS-500 screen faded badly in the time that I had it. I've seen no reports of it with modern eInk screens. and certainly none of the devices I've bought in the last couple of years has shown the least sign of screen fading. I think you can safely buy a modern eInk device and be sure that the screen won't fade.

The "2nd generation" Kindle DX (the "Graphite") uses an eInk Pearl screen. I've seen no reports of fading issues with Pearl screens, so if you wanted a replacement DX that should be a safe choice, although there are certainly other more modern large-screen devices available, such as the Onyx M96.