I agree with icallaci. I use all of mine fairly regularly as this will possibly keep the battery better. (although I do have a favorite
) Plus if one is going to fail it might still be under warranty.
For me there are advantages to being able to switch readers. I sometimes want to change the book, but don't want to abandon it for instance. Leaving it 'open' and switching readers makes it more likely I will pick it up soon. And I like to keep a third separate reader in my backpack so I won't forget it at home.
Helen