But I hear enough through the woodwork that I have been under the impression using Kobo would be trading off annoyances with some things better & some worse. Mostly what I hear is Kobo often has some hardware advantages but has some different software annoyances.
What format the book uses is a very minor concern to most of us who just read the books. Epub vs Mobi vs KF8 or whatever has no impact on me 99% of the time. The only time it'd really matter is hopping around between platforms and having to convert stuff.
If Kobo started having a huge advantage I'd be more likely to buy a Kobo and keep my Amazon library with Amazon and start buying Kobo books there. I wouldn't go on a big project to convert all my Amazon bought books to a Kobo compatible format. Cause once done I wouldn't actually need/want to re-read all those books on the Kobo.