[dioib]

I think as long as you're only working with normal text with no symbols, a 6 inch device is as good as enough. After all you can zoom the text and popular formats support reflow. With rich documents that contain graphs and perhaps more sophisticated substructures it's a different story: you can zoom but at the price of spending too much time rolling the display around the page and with the low refresh rate of dedicated displays, it is not, in any rate, practical. THERE I think bigger displays are going to make a positive difference (for otherwise the {affordable/manageable} smaller is, usually, the better) and in that case, between 8 and 9.7 sizes the latter rhymes better with reason.