Does anyone have experience using an e-reader to consume a service like this?
The irony is that the page flip skeuomorphism works for eink because when you flip a page, you expect to go to the origin of the next page once the flip completes. E-readers do this, and it works as long as you don't try to animate it because of how slow eink is. The pgdown/pgup mechanism leaves the last few lines on the screen, which works well when you can animate the scroll action, since your eyes can follow it. But again, eink is too slow for this to work well.
I complained to O'Reilly about this, but they gave me a boilerplate response that they take user feedback seriously. I don't know if it's been fixed.
What I do now is use a Python package that converts O'Reilly learning books to epub. You need a login to use it (of course), and it would certainly be beyond acceptable fair use if you distribute the generated epubs beyond your own devices.
That would at least get you a laptop-sized screen.