When we home-schooled the kids, I bought a Kobo because most of the books on their reading list were out of copyright and I could download then for free.
I do prefer paper books for long term.
I have used Amazon Kindles for years, but I turn off the Internet update function as soon as I get them and never buy ebooks from Amazon. I either download free ebooks or buy them from other sources (usually in .pub format). I convert them to Kindle format and upload them from my PC to my Kindle using a free program called Calibre.
I highly recommend Calibre to anyone who has ebooks.