I would like to ask some people with older eyes. I have a 3 1/2 year old Kindle DX and thinking about upgrading to a Paperwhite for the better resolution. My DX has radio but I keep it turned off to get max battery life. I do read it all the time but I was thinkiing that with a better resolution it would be easier on my older eyes. Would go with a Wifi model as Wifi is everywhere here. What are your thoughts about this.