I have now moved to bifocals myself and have no problems whatsoever reading my Sony. The only eyestrain I get is if I don't stop reading after 8 hours, but not sure if that has to do with the reader

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I find reading the Sony like a book. Sure, there is a bit of glare but it doesn't bother me all that much. And on days when my eyes or my head is a bit tired, I just increase the font size.