I got the black and white Clara, not the color version...I have no need for color when I read, so I didn't see any reason to spend the extra money.

I do use Apple Books occasionally, and it works very well. The greatest pain point in all this is that the Clara doesn't sync with Apple Books (or anything else except things purchased off the Kobo bookstore), so if I want to read something on the Clara as well as Apple devices, I have to remember and find my place manually. (And I did read your linked article when it first came out!)

It's unfortunate that the ebook market is so fragmented and incompatible, but this is where the world is!

Another thing in favor of the Clara is that it includes Libby, the public library lending app (so probably not relevant outside the US) and Pocket, which is my favorite offline reading app.