Honestly, the Kobo N647 never seemed like the sturdiest eReader around. Even when it was Kobo's primary device there were always better devices on the market. It seems like the new generation of Kobo eReaders are more durable than the first model Kobo reader. Still, I imagine there are people who still own working models of the Kobo N647.
As with any electronic gadget, there are some duds that make it to the market. Fortunately, for me, the majority of my gadgets, including my Sony PRS-350 have held up quite nicely. I had one Nook whose screen went kaput after 24 hrs. B&N replaced it and I never had any issues with the replacement.