Welcome to MobileRead, tsanta.
Here is our Wiki on dedicated ebook devices, maybe this might help with your decision.
https://wiki.mobileread.com/wiki/E-book_devices
As for the Kindle, there is no place to 'demo' it. However, you do have a 30 day unconditional return policy. Buy it, download to your hearts content, (free ones from here maybe? ) check it out thoroughly............if its not what you want/need, return it paying shipping only.
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