After a few days to read, read, read and finally read this forum I finally managed to buy a Kindle Voyage.
It was hard to decide. I longly hesitate between Glo HD / Glo Aura H2O.
Frankly, after seeing the Kobos in store, it wasn't possible to go to the Glo HD as it looked cheap compared to my actual Sony PRS 650 (Witch looks like to be new after 5 years)
So, I'll give a chance to the Voyage, which seems to be a beautiful device (impossible to see it in stores in France) and I'm now very impatient to receive and read with it.
I won't forget to put my impressions here.
By the way, thanks a lot for all your posts. That was very pleasant to read and helped me.