I have a kindle paperwhite, i get around the ads by not connecting it to the internet, and i can sideload books by dragging and dropping or using Calibre. But nice offering by B&N
Onyx Boox are basically android tablets with e-ink that you can enable Play store on.
I tried a couple of display models in stores and it seems quite responsive. Couldn't justify the price though since I've a backlog of books converted to epub that will take me a decade to get through.
