The iPad measured at 6.2% lower reading speed than the printed book, whereas the Kindle measured at 10.7% slower than print.
After using each device, we asked users to rate their satisfaction on a 1–7 scale, with 7 being the best score.
iPad, Kindle, and the printed book all scored fairly high at 5.8, 5.7, and 5.6, respectively. The PC, however, scored an abysmal 3.6.
via useit.com