So, first impressions are that it is heavy, good thing you dont have to move it around much :). The keys take a bit of getting used to as they do not depress far and are shaped to be higher on the edges. When you first plug it in it will be all one colour, (blue for me), but the WOW comes when you install the software (available on the logitech website). The keyboard immediately did a good impression of a moving rainbow. I do have a bit of a criticism in that you cannot change the color scheme with the m1,m2, and m3 buttons like you can on older keyboards. However, you can configure it to change itself to change color profiles when you start certain games/programs. The arx control dock was not what I was expecting, though that was really my fault for not reading the material enough. All the dock does is hold your phone, the keyboard then accesses the phone wirelessly.
Another thing to note is that the keyboard is quite tall. The first palm rest is not very good, but the second one that comes with it helps a lot.
i wont put this on pros and cons as it is both, but the new keys seem to sacrifice some typing control for gaming control.
Pros: Comfortable Cool lighting and Effects Nice keys Has a media control dock for windows media player and Youtube. Keys are good for 70million presses.
Cons: Heavy A bug in the software means that the Num lock, scroll lock, and caps lock indicator lights do not work properly in some lighting modes. Expensive