Not the person you replied to, but I've had 2 kobos and didn't have a problem with either. (The screen on the first one broke, but that was my fault for dropping a book on it. I might have been able to fix it if they had this ifixit deal back then)

I have had two for many years and both are working fine. I bought the second because they introduced a waterproof version. Still use both 10? years later. This could tip me to buying a third with colour.