I was leery of the Kindle because of liking the physical feel of a book. When I ordered mine, I got
this cover for it. Though I didn't realize it at the time, that totally solved the problem (for me at least).
I have tons of pdfs on it as well, and use it on a daily basis. For me, there is zero eye strain, and that is not the case after looking at a monitor all day long.
I didn't really explore other options because I wanted a dedicated reader. When I'm using it, I don't need the reminder that I could be/should be working. I wanted something that was purely for pleasure.
I have a DX, and I would buy it again.