I have a few of these Kobo Touch readers that haven't been touched in years, so no idea if the batteries even still work. Even though I'd never tried them before, I got 3 as a local shop (WHSmiths in the UK) was having a clearance sale as they were being discontinued, so I got 3 of them for less than the price of 1 would normally cost, and I'd read they were quite hackable.
I really liked the idea of using them, and while I did take one on holiday once, I found that I just couldn't put up with the slow speed of page transitions and the screen flickering every page turn.
For the speed issue, if it's limited by the time to render a page, I wondered why they wouldn't just cache the rendered previously page and pre-generate the next page while you were reading the first.
I understand why the page flickers, but it always seemed to me that doing partial refreshes of the screen would be much better aesthetically. Maybe the more recent ones actually do that, although I got the impression that manufacturers had just moved back to LCD screens because people liked colours more than battery life. Certainly not long after I bought my Kobo, my mum upgraded from an e-ink Kindle to an LCD one which seemed like a step backwards to me, but she was much happier with it.
So, just wondering if any of the issues around page turning are addressed in this custom OS and app. If so, I'll dig around in my junk box to try it out. Otherwise I guess they're likely to stay there for another decade!