If you're just talking about a normal book, i.e. not picture book, pop-up book (!) etc then the content of the Kindle edition pretty much replicates the content of the printed version.
Note I say "content", not "layout". The layout, page numbering etc changes according to your settings on the Kindle, because you can change the size of the text to suit you.
One lesson I've learnt from having kids who play computer games on lots of different platforms - in the end, the cost of the platform (Kindle, Sony, Kobo etc.) is a small part of what you pay to digest the content on the platform. So my advice would be to get a Kindle if you've seen lots of books on Kindle that you like, and likewise for Sony eReader and Kobo if that's the case. Don't feel you're tied to only one. That said, I have a Kindle and it's met all my needs so far...