I only have 2 devices that I read on - my KA2 and my Kobo Mini. I kept the mini because it fits anywhere. I have owned 5 devices other than those two. When I get a new primary reader, I will wipe my old one, load it up with a ton of PD books, and donate it to my local kids/teenagers hospital. No need for me to have piles and piles of readers I don't use.
Those readers get to live on that way