Philipdk,
I know you didn't ask for any advice here, but if you are interested and you share why you are getting your reader, I'm sure you will get lot's
of opinions to help you out.
The devices you posted look interesting , but I'm not sure that they contain the right combination of features for me. Of course, as I said your specific uses will be different than mine. However, if I was considering buying them, my biggest questions wold be in 1) the maturity of the software/interface, and 2) the hardware quality (especially of the screen).
Unfortunately, these are the hardest things to judge over an online page.