It is me again, sorry for the double post.
So, it is done: I've bought a Kobo Mini

I am discovering it since Sunday, so everything is still new and unknown. So far, I like its size very much. That is so convenient to hold the reader with one hand, without any unnecessary tension in the wrist
I will get back to you as soon as I am more accustomed to this little guy.
Many thanks to all of you for your nice inputs