The processing of the keyboard is good, only affects the transparent plastic frame around it is not necessarily very high quality (creaks ever).
Before that I had a wired 'Cherry evolution Stream' that the writing experience and the volume while typing even now would I still prefer, but I wanted to banish the cable from your desktop and have the opportunity to take keyboard and mouse with the couch when I the TV as a monitor use.
The keyboard could be so happy to be a little quieter but otherwise I am absolutely happy with it.
I notice no delay in the entry (even during fast action FPS games or about Pinballsimulationen) and had previously never under the impression that inputs had been 'swallowed' - the transmission works perfectly (receiver is under the table at the front of the computer USB , Keyboard is on the table or in ~ 3 meters distance to the receiver in front of the TV).
About the security of the transmission one learns unfortunately very little, except that there are probably a "128-bit (AES) encryption between device and receiver" are.
The installation is very simple and also the pairing of another mouse (Logitech M705) with the Unifying USB receiver was easily.
I've tried other wireless keyboards in various markets and ultimately is my MK520 best.
In addition, Logitech scores clear with the Unifying technology, so you can run more than one device at a receiver manufacturer.
Still, I would have liked that you could buy the keyboard without using the mouse, because for me it was clear from the beginning that I would not use them.
