No backaches. But I read either reclined with the DXG resting on my belly or I place it on my desk. It can cause my arms to get tired if I try to hold it without somehow resting it on something. I mostly use it for reading large format PDFs so it isn't a problem to place it on my desk since I'm usually taking notes and looking up references from other sources. I don't think I would want to use the DXG for all my casual reading. For me it is a special purpose reader to help me in my research.

It does make me wonder about the iPad though as the iPad is 1.5 times as heavy. Other tablets are at least that heavy. If people use them for all their reading they might develop Pop-eye arms! Or more likely, we will see a whole set of muscular and skeletal conditions arise and eventually be called the tablet syndrome. Texting has caused carpel tunnel in many teenagers. So it will be interesting to see what the long-term medical implications are for tablets/slates.