Actually, I confess to having a Kyocera Echo, though I don't carry it much. It's more of a placeholder for my Sprint account and an answering machine for the people like doctors who refuse to update their files to list my other number.
Kyocera has done a not-terrible job of getting apps not designed for the crazy format (which is 99.9% of apps, of course) to work decently across two screens.
As for Windows, the rallying cry seems to be "Just you wait until Windows 8!" But that's going to be a while. I've been using a
tc1100 convertible tablet as my desktop machine for the past year. Just took it out of service, actually.
It came with XP Tablet Edition, and I upgraded it to Win7. When it wasn't docked with a keyboard and mouse - when I used it as a tablet - my main complaint about touchscreenability had to do with the 8-year-old screen technology rather than with the OS.
The
Asus EP121 doesn't seem like a bad Wind machine though maybe a bit big at 12.1"....
-- Ed