It's mainly just the little things like button placement, (or lack thereof on the PRS-600) that I've gotten used to with the PRS-700, although there is a difference in clarity, the issue never bothered me too much to begin with. I find that in terms of usability, I prefer PRS-700 over the 600.
And overall, its almost the same exact reader, so it's also pretty hard to justify an additional $299 purchase.
Now all I want is a firmware update for 700 for dictionary.
