[wildstar]

I have both the original Kobo and a wi-fi K3.

Everything on the K3 is faster. Page turns feel instant, no need to push the page turn button a few words before the end of the page like on the Kobo. To be honest, if you are going from one page to the next while reading, the difference is not significant. Where it does come into play is when you are flipping through pages. You can flip through pages on the Kindle, it's pretty painful on the Kobo. Also important is that general navigation of the book via chapters, table of contents, text search (which the Kobo doesn't even have) is also very fast. So is opening books from the home page. The kindle also reads hyperlinks used in footnotes. Before I got the K3, I was reasonably satisfied with the Kobo's speed. But once you start using the K3, the Kobo feels pretty pokey. Hard to go back. Also, you can set up Calibre to email your ebook to the Kindle's email address, giving your Kindle wireless delivery. Very slick.

Once you have the DRM removed, I have had no problem converting epub to mobi using Calibre. In fact, I have found that the epubs I buy from Kobo, once converted and put on my Kindle, look better than they do on the Kobo. Zero problem with tight margins, oddly formatted chapter headings, large line spacing etc, which I have had with several epubs on my Kobo. I buy my ebooks almost exclusively from Kobo for reading on my Kindle. That's my experience at least.