There are two aspects here – screen refresh & responsiveness.
The screen refresh is very quick. So much so that when reading text files I sometimes don’t notice that the screen has changed! I find that by the time my eye has scanned to the top of the page, it’s fully updated.
Secondly is how responsive it is. For text files, epub and HTML it’s very quick. PDFs are a bit slower – if they’ve got lots of images or you’ve set it to reflow it can be a little annoying. That’s simply because the device is doing more work to calculate what’s on screen. It’s not unbearably slow, but it is noticeable. So, I guess it depends on the sort of texts you’ll be reading.
I have noticed that it occasionally misses a turn. I’m not sure if that’s me not pushing the button properly or a bug. Either way, a quick tap gets it going again.
The font is very readable. It has “Arial” or “Latin” each of which can be set to “Clear” or “Smooth”. I find Clear Arial to be perfectly readable. Very easy on the eye.
Finally, how often you turn the page depends on the font size. On the largest font size, you get about 40 words to the page over 10 lines. On the smallest, it’s about 180 words per page over 20 lines. You can adjust the line spacing to give you a greater or lesser number.
There are about 350 words per page on an average paperback. That said, I don’t really notice that I’m continually thumbing the button.
I’ll try & post a video this weekend showing the refresh rate.