That is a much more reasoned stance than your first post indicated. As someone who engineers manufactured products for a living (and troubleshoots customer returns), let me make a few observations about e-readers.
They are portable so they are subject to much harsher environments than your TV or fridge. They will be temperature cycled every day (left in a car, read outside), dropped "x" times every year, vibrated in transit ('trains, planes and automobiles'), and splashed with household materials (from cleaners to drinks).
The charging connector will be rammed in once every two weeks or so. We already know the battery will only be good for so many charges (with diminishing capacity likely in a year or two).
I'm not so worried about the buttons because microswitches are a very mature technology but the printing on buttons is likely to fail sooner. Would that be a warranty item?
We (I) do not know the lifetime of Visiplex e-ink nor its failure modes. Is it only good for "x" page turns? Do random pixels drop out? Do we lose entire rows or columns? Do we lose contrast (ink not separating or the pigments fading)?
Not knowing more, I would probably be most concerned about temperature cycling and vibration. The weak link in most electronics are connections. Solder joints fatigue and break. Pressure contacts fret. Crimps corrode or loosen. Heaven help us if these new readers are "lead-free" devices! Pb-free solder joint durability is much more dependent on proper processing (narrower process window) than traditional tin-lead solders.
By the way, if a particular model is NOT Pb-free that might be a reason why it is not sold in Europe. Their RoHS legislation is in full swing.