Pocketbook is what you want. For some reason not popular state-side, but it's absolutely the bees-knees. Drag and drop install of Koreader. Built in RSS read

Pocketbook is what you want. For some reason not popular state-side, but it's absolutely the bees-knees. Drag and drop install of Koreader. Built in RSS reader. Performant PDF reader (if you want to not use Koreader) Linux, so you can write your own stuff if you want. I own the Era model, and it's been amazing.