I love mine, it's mostly opened up so you can sideload almost whatever you want (EPUB , CBR/CBZ, PDF although not great, and even Kiwix ZIM files) and there is a great modding community on mobileread.

I found the integration with Pocket (read-it later kind of servixe) to be quite useful, as I can read web articles at my own pace, without any distractions on a paper-like display without requiring Internet access.

I'll second the Kobo. I moved over to them after owning several Barnes & Noble's Nook e-readers and couldn't be happier. I have purchased several for others as gifts (which is better than just a recommendation!). I can check ebooks out of the local library with the integrated Overdrive (functional and free, limited catalog), occasionally buy books from the Kobo store (convenience), but often purchase DRM free epubs (Baen Books being a favorite for Sci-fi/Fantasy) and sideload them.

I love mine and use one every day (and have for years now).