If a PC USB keyboard works, then the K400 works. I have not seen the K400 Plus so buy it on say Amazon Prime.
Compatibility? Horrible. One of the not-so-smart things about the Smart TV apps is that keyboards may not work. And Samsung doesn't write all the apps so if you find an app that the keyboard doesn't work, well, good luck getting it fixed. The YouTube app was notorious about that.
That said, the web browser is somewhat OK (except for sites that don't work) with the keyboard.
In closing. Adding a keyboard does not turn it into a PC.
Just looking for further input:
My UN40JU640DFXZA does not support Bluetooth and it was suggested to me in a previous post to go with the Logiteck K400 keyboard (USB dongle config). Can anyone else expound on compatibility? Would the newer Logiteck K400 plus work as well?
Think I'm headed in the right direction. Thanks!