There’s a very long forum post evaluating various aspects of tablet screens and their suitability for long-term reading [Google English]. What’s interesting is that in all of the categories, the iPad 4 wins. However, it also mentions that for many Chinese eBooks — which are actually scans of the original paper — even a 9.7-inch tablet screen is too small. It seems some printed Chinese books — or at least the ones this guy wants to read — are large.
The same person does another forum post comparing three different tablet screens, with photos [Google English]. What’s interesting about this post is that even Google Books is mentioned (everyone who thought I was alone in my Google Books obsession: Ha!).
I’m not sure if these posts are relevant to readers of non-Asian texts but I still found them informative for bringing up issues I hadn’t considered, such as “warm” versus “cold” screens. Anyone interested in using a tablet to read PDFs might want to read these posts as an additional aid to choosing a tablet.