I’ve had an Oasis since 2017 and I generally like it. I am not crazy about all my e-books being hosted in the Amazon cloud. But I made that bed over a decade ago, and will have to lie in it. I do love the convenience of e-books, too.
One thing that annoys me about Kindle is that if it can’t connect to the Amazon cloud for some reason, it will burn through the battery pretty quickly as it desperately tries to connect over and over again. This is an issue in my house, because my WiFi is filtered by a Pi Hole. So I end up leaving my Oasis in Airplane Mode most of the time. The battery lasts a lot longer that way. When I want to sync or download a new e-book, I just take it out of Airplane Mode for a couple of minutes.